Anyone Using an Asus DSL-AC68U

Well something happened on the 612 today, and it's knocked me onto interleaved 24 hours after swapping it from the Asus.

Now also knocked down to 56/16mb. Swapped back to the Asus for the time being, and weirdly MAX Rate Down is now an easy 10mb higher than previously, could that be something to do with being interleaved?


Code:
ASUSWRT DSL-AC68U_3.0.0.4 Mon Jan 12 06:52:14 UTC 2015
admin@DSL-AC68U:/tmp/home/root# cat /tmp/adsl/info_adsl.txt
outDiscards=0
inDiscards=5
outBytes=6346090
inBytes=225646398
outPkts=79071
inPkts=151445
fwVer= FwVer:5.5.1.126_B_A60901 HwVer:T14.F7_0.2

lineState=up
Opmode=ITU G.993.2(VDSL2)
SNRMarginDown=6.1 dB
AttenDown=10.9 dB
SNRMarginUp=5.9 dB
AttenUp=3.0 dB
DataRateDown=56342 kbps
DataRateUp=16424 kbps
WanListMode=0
FECDown=360
FECUp=50
CRCDown=0
CRCUp=0
HECDown=0
HECUp=0
ADSLUpTime=6 min, 27 secs
ADSLActiveTime=0 min, 17 secs
PowerDown=13.8 dbm
PowerUp=6.8 dbm
ATURID=26005443434e0000
ATUCID=b5004244434da485
AttainUp=20630
AttainDown=82920
ShowtimeStart=17
TotalStart=35
ATURANSIRev=0
ATUCANSIRev=0
ATURANSIStd=0
ATUCANSIStd=0
InterleaveDepth=815
AdslStandard=VDSL2
AdslType=ANNEX_B
mtenStandard=G.dmt.bisplus (Annex L)
admin@DSL-AC68U:/tmp/home/root#
 
Hello all, sorry to change the subject slightly, but it'll only be brief!

I bought the DSL-AC68U to connect my Virgin Media Fibre Optic and BT ADSL connections. I went with the DSL version to reduce the number of unsightly boxes lying around by one (despite the BT HH4 being the best looking of the bunch!). Everything is working fine with both connections, and they seem to switch over even on Load Balance mode. I'd prefer to be using Failover mode, with my primary line as my fibre from VM (through a LAN as WAN port) due to its high speed, and I wanted my BT ADSL to be secondary for the many times my VM disconnects (endless faults in my area but I like the DL speed when it works), however the AC68 only seems to like the connection through its internal modem to be primary. Current firmware is 376.2050, will an update to this allow me to set a WAN connection as primary? I don't want to go messing around with it too much in case I need to return it and swap with the RT, so thought I'd ask the experts first!

Extra info, Load Balance seems to favour the VM connection (seen by using speedtest.net), and I have the ratio set as Primary 1 : 4 Secondary, hoping it will make the secondary virtually act as primary. I've tried browsing and disconnecting the VM superhub and browsing was uninterruped as it automatically started using the BT, but I have a feeling it won't work if the hub goes down due to a line fault with the hub still connected to the ac68. Does the Load Balance mode also act as failover if this happens? If it does then I might not need to change to the RT.

I have a feeling from all the comments here though that I may as well swap for the RT and let the BT hub handle its own connection, especially if BT decide to upgrade my area to its fibre service any time soon.

Thanks for any info you guys can give me on this!
 
Hi everyone - PlumpMonkey pointed me in the direction of this thread a short while ago and I'm trying to get a handle on what's happening here.

So as far as I can tell, some of you are having issues with the VDSL modem which aren't replicated on other modems i.e. the BT HH.

The symptoms are CRC failures on the download which you can see in the logs, slower than expected speeds detected and slower than normal pings on trace routes - does that sound correct?

The more info I can get on this, the better when I contact the technical team but it's hard to summarise such a long thread accurately so I'd appreciate your help to make sure we get this sorted properly.
 
Hi everyone - PlumpMonkey pointed me in the direction of this thread a short while ago and I'm trying to get a handle on what's happening here.

So as far as I can tell, some of you are having issues with the VDSL modem which aren't replicated on other modems i.e. the BT HH.

The symptoms are CRC failures on the download which you can see in the logs, slower than expected speeds detected and slower than normal pings on trace routes - does that sound correct?

The more info I can get on this, the better when I contact the technical team but it's hard to summarise such a long thread accurately so I'd appreciate your help to make sure we get this sorted properly.

Hi Jim,
Welcome to the forum, it's nice to see an official ASUS representative on here.

Yes, those suffering with stability on VDSL2 connections have abnormal FEC errors (if interleaved) or CRC errors in comparison to other devices used. In my case I've used the Fritz!Box 7490, the Huawei HG612 and ECI /i and /r (Huawei and ECI's are supplied by BT), none of them exhibit the same issues that I'm experiencing when using the ASUS DSL-AC68U. As a result of the abnormal CRC's, DLM eventually kicks in as it sees instability and so increases the error correction to a rather high level and bands the downstream sync rate to a lower speed (e.g. on the ECI /r I was 74Mbps fastpath, now I'm 49Mbps interleaved with INP 7 on a delay of 16ms since using the ASUS DSL-AC68U).
 
Hi Jim,
Welcome to the forum, it's nice to see an official ASUS representative on here.

Yes, those suffering with stability on VDSL2 connections have abnormal FEC errors (if interleaved) or CRC errors in comparison to other devices used. In my case I've used the Fritz!Box 7490, the Huawei HG612 and ECI /i and /r (Huawei and ECI's are supplied by BT), none of them exhibit the same issues that I'm experiencing when using the ASUS DSL-AC68U. As a result of the abnormal CRC's, DLM eventually kicks in as it sees instability and so increases the error correction to a rather high level and bands the downstream sync rate to a lower speed (e.g. on the ECI /r I was 74Mbps fastpath, now I'm 49Mbps interleaved with INP 7 on a delay of 16ms since using the ASUS DSL-AC68U).

Same story for me, the Asus had to go back and I'm now running a Billion 8800NL Bridged into an Asus RT-AC68U. I really hope you can sort this as I would love to go back to the Asus.
 
Hi everyone - PlumpMonkey pointed me in the direction of this thread a short while ago and I'm trying to get a handle on what's happening here.

So as far as I can tell, some of you are having issues with the VDSL modem which aren't replicated on other modems i.e. the BT HH.

The symptoms are CRC failures on the download which you can see in the logs, slower than expected speeds detected and slower than normal pings on trace routes - does that sound correct?

The more info I can get on this, the better when I contact the technical team but it's hard to summarise such a long thread accurately so I'd appreciate your help to make sure we get this sorted properly.

Hi Jim and your input is much valued in here and at last a asus rep, hooray, however, as I keep stating, mine never had high crc's what so ever and still it caused issues that forced me onto interleaved even on a 40mbps connection, fec's were as high as anyone else though. Put the open reach modem back and within days my connection was back to normal. You are correct though that my pings were high and my speeds slower with the asus. To be honest so many have come in here thinking they might be able to work something out and then been defeated I have given up hope of any solution. However I will leave it with the experts here to converse with you as they have done the testing and seem to understand the techie speak more than I do...
 
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I think half the blame can be pointed to the DSL settings page which shouldn't exist in the UK as it can and is being used to over-ride DLM settings. This would surely violate BT's SIN specifications for both VDSL and ADSL in the UK. There is no way of knowing what some of these these should be set to, simply because they don't exist on any other DSL device currently on sale within the UK off the shelf.

The sheer volume of FEC errors (100x more per second) being reported by this device whether its a hardware or firmware problem is without doubt why nobody seems to be able to maintain a stable connection and move from an Interleaved connection to a Fastpath due to DLM.
 
I think half the blame can be pointed to the DSL settings page which shouldn't exist in the UK as it can and is being used to over-ride DLM settings. This would surely violate BT's SIN specifications for both VDSL and ADSL in the UK. There is no way of knowing what some of these these should be set to, simply because they don't exist on any other DSL device currently on sale within the UK off the shelf.

The sheer volume of FEC errors (100x more per second) being reported by this device whether its a hardware or firmware problem is without doubt why nobody seems to be able to maintain a stable connection and move from an Interleaved connection to a Fastpath due to DLM.

I disagree with that. The settings page even with default settings is still causing instability.
 
Hi everyone - PlumpMonkey pointed me in the direction of this thread a short while ago and I'm trying to get a handle on what's happening here.

So as far as I can tell, some of you are having issues with the VDSL modem which aren't replicated on other modems i.e. the BT HH.

The symptoms are CRC failures on the download which you can see in the logs, slower than expected speeds detected and slower than normal pings on trace routes - does that sound correct?

The more info I can get on this, the better when I contact the technical team but it's hard to summarise such a long thread accurately so I'd appreciate your help to make sure we get this sorted properly.

Hi Jim. Thanks for looking in.

As others have already said, this modem seems to be incredibly unstable for a large number of people on VDSL connections in the UK.

For my particular case I can run on the BT supplied HH5 at a 70/20 sync rate for weeks on end with no disconnections or problems. However switching to this modem causes nothing but trouble. I have tried various firmwares, both official and beta, yet I cannot hold a stable connection for more than a few hours.

DLM then kicks in very heavily the next morning and throttles my connection down to about a 40Mb sync with a SNR of >16, yet the stability issues still persist even at this much reduced rate. At this point I usually give up for fear that my speed will get throttled further as it takes DLM about 6 weeks to restore my sync rate from this point back to where it should be at 70Mb.

The last time I had contact from Asus technical support they suggested that the disconnects were due to a noisy line, yet the HH5 has no problems at all maintaining connection at the higher sync rate and a SNR of ~6.

There are a lot of people on this thread who have tried to be patient with diagnosing these problems but when we are crippling our own connections for months on end to perform this testing, this is starting to wear thin.

This is obviously a problem with the Asus device as so many other modems work (HH, Billion, Fritz, ECI) where this one doesn't. To have technical support deem this as a noisy line problem is just not on. This product is just not fit for purpose for VDSL and is causing a lot of bad feeling for such a premium product.

I have a lot of Asus gear (MB, wifi points, etc) which I have never had a problem with. However the level of support received on this issue is really starting to put me off considering asus going forward. The is the first time I've needed Asus support, and it is sorely lacking.
 
Hi Jim. Thanks for looking in.

As others have already said, this modem seems to be incredibly unstable for a large number of people on VDSL connections in the UK.

For my particular case I can run on the BT supplied HH5 at a 70/20 sync rate for weeks on end with no disconnections or problems. However switching to this modem causes nothing but trouble. I have tried various firmwares, both official and beta, yet I cannot hold a stable connection for more than a few hours.

DLM then kicks in very heavily the next morning and throttles my connection down to about a 40Mb sync with a SNR of >16, yet the stability issues still persist even at this much reduced rate. At this point I usually give up for fear that my speed will get throttled further as it takes DLM about 6 weeks to restore my sync rate from this point back to where it should be at 70Mb.

The last time I had contact from Asus technical support they suggested that the disconnects were due to a noisy line, yet the HH5 has no problems at all maintaining connection at the higher sync rate and a SNR of ~6.

There are a lot of people on this thread who have tried to be patient with diagnosing these problems but when we are crippling our own connections for months on end to perform this testing, this is starting to wear thin.

This is obviously a problem with the Asus device as so many other modems work (HH, Billion, Fritz, ECI) where this one doesn't. To have technical support deem this as a noisy line problem is just not on. This product is just not fit for purpose for VDSL and is causing a lot of bad feeling for such a premium product.

I have a lot of Asus gear (MB, wifi points, etc) which I have never had a problem with. However the level of support received on this issue is really starting to put me off considering asus going forward. The is the first time I've needed Asus support, and it is sorely lacking.

Thanks for all of the info, PM and others, much appreciated.

My very early understanding is that it was hoped firmware updates would fix this problem, but it's clear that's not been the case so I'm now chasing it up with the responsible department. I'll do my best to find out some useful information and keep you all in the loop, though just to avoid any disappointment I can't guarantee it will be quick as we don't work in the same office.
 
Thanks Jim, as we have been perservering with this modem for months I am sure a few weeks won't hurt. I, though, will not be reconnecting mine to the dsl until I am 100% certain it'll be stable.
 
Exactly. The last time I tested this modem was 20th Jan. I got knocked down from 70Mb to 40Mb. DLM only restored me to 59Mb two days ago so its probably another week or two before I'm back to where this line can handle it on a stable modem.
 
I think half the blame can be pointed to the DSL settings page which shouldn't exist in the UK as it can and is being used to over-ride DLM settings. This would surely violate BT's SIN specifications for both VDSL and ADSL in the UK. There is no way of knowing what some of these these should be set to, simply because they don't exist on any other DSL device currently on sale within the UK off the shelf.

The sheer volume of FEC errors (100x more per second) being reported by this device whether its a hardware or firmware problem is without doubt why nobody seems to be able to maintain a stable connection and move from an Interleaved connection to a Fastpath due to DLM.

BTs SIN or suppliers information note is nothing more than recommendations to providers. There is nothing to "violate" becuase it is far from officlal or independent testing. Asus building a device with access to settings are not in the wrong... BT are in the wrong for either A) Not supporting certain settings properly B) Not disabling certain functions they do not want tampered with at the line card/DSLAM c) The "recommendations" are meaningless as their VDSL complete with their own custom DLM does not follow ITU spec and they are the organisation who should be followed.

The FEC thing is clearly a bug with the device, Asus i agree need to fix that. HOWEVER and here is the rub. Even if that is causing people to be DRM'd then the actual thing that is causing the reduced speed is the DRM system, and again that is BTs if the DRM system (an non official non ITU approved system) was not there, then there would be no issue. You would not blame a tap manufacturer for issues if you bought a new hot water tap with a standard pipe fitment/thread and the water board in your area decided to use a different sized thread on the pipes so your tap wont work/fit would you, even if it worked all over the rest of the world or the country at the least????

I disagree with that. The settings page even with default settings is still causing instability.

But thats just it, what should the default be for BT DSL services?

The settings are irrelevant. BTs FTTC has clearly been tuned to perform at its optimal with certain chipsets Lantiq (as seen in ECI modems) and Broadcom devices (as seen in the Huawei modems) as supplied by Openreach. Again no matter how buggy a device is that is wrong, even more so when BT plan on not supporting or replacing faulty modems they supplied in the not too distant future. Oh and now there is also self install services from providers which do not supply modems with the product. Why should the consumer have to do stupid amounts of research to ensure they buy a box with a chipset that is suitable and performs optimal to a specific service?

The Asus is far from perfect, you can even argue its less reliable than every other device if you wish, it has bugs, we know, we get it, no device is perfect though so you are stating the obvious.

The real question is... If the device works ok in other areas of the world it can not be faulty hardware (its either faulty or it is not), If you are arguing faulty hardware works ok in say Timbuktu but not in the UK, then there must be a reason for it and its more than likely due to the way the service is setup/configured at its core and again that comes back to BT. The very fact that if you over-ride the DLM system with the device and it then gives you full speed (as ixel has proven) shows half the issues are the DLM system and only another 50% at best are issues with the Asus device. Fixing one without the other will still leave you with a 50% broke system, so leveling all the blame at just the ONE organisation is IMO silly.


I suspect this can be fixed with firmware however due to the chipset any change Asus make, may render a device that performs perfectly here in the UK but not in other areas of the globe. Of course they could do this and have UK ONLY firmware, something id personally like to see and the UK offices (or nearest in Europe if they have them) take responsibility in this regard, hopefully now a Asus Rep has appeared things may progress quicker. Its too bad the COMPLETE firmware is not open source or similar (INCLUDING THE MODEM PART) i suspect if it were then by now on forums like these people such as myself would had ripped into it and tried various things until it was fixed.... Theres a reason things like DDWRT are so popular have so many functions and broken things get fixed... Its the sheer numbers that play with the code. Poor Asus for all we know in the UK/Europe may only have one poor code guy locked in the cleaning cupboard ;)
 
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The real question is... If the device works ok in other areas of the world it can not be faulty hardware (its either faulty or it is not), If you are arguing faulty hardware works ok in say Timbuktu but not in the UK, then there must be a reason for it and its more than likely due to the way the service is setup/configured at its core and again that comes back to BT. The very fact that if you over-ride the DLM system with the device and it then gives you full speed (as ixel has proven) shows half the issues are the DLM system and only another 50% at best are issues with the Asus device. Fixing one without the other will still leave you with a 50% broke system, so leveling all the blame at just the ONE organisation is IMO silly.

Although I agree in principal, I disagree. :) The UK VDSL market has a very small number of providers. If someone wishes to sell a device that is purported to work with it, the burden of providing interop testing and proving the thing works in that market is up to them, not BT. Saying its BTs fault for being different to the rest of the world with their DLM implementation doesn't cut it. Asus have decided to sell a product in the UK that's touted to work on VDSL. It doesn't. I don't care if its works in Timbuktu or not, I don't live there and I dont want to use this modem there. It doesn't work well in the UK, and that is where ASUS have sold me this device for use.

Using a poor analogy, left hand drive cars work very well in most of the world, but they arent so effective over here. It doesn't mean its a poor car though. It's up to car manufacturers to tweak their product to work the best in this market, and that means moving the steering wheel to the other side.

Asus failed to perform a decent level of interop testing on this product before releasing it in this market. The fault squarely lies at their door for this one.
 
Hi All.

Quick related question.

I am planning on buying the RT-AC68U and use my existing providers modem in conjunction with the router.

Are the issues mentioned in this thread only impacting the DSL version, which has the modem built in to the device?
 
Hi All.

Quick related question.

I am planning on buying the RT-AC68U and use my existing providers modem in conjunction with the router.

Are the issues mentioned in this thread only impacting the DSL version, which has the modem built in to the device?

Its a great modem, highly recommended especially with the Merlin firmware.
 
Well mine arrived yesterday and frankly it sucks. Got it connected on Plusnet FTTC and managed to update the firmware, I suspect it was actually more stable on the original firmware. Then it was repeatedly dropping connection, often in mere seconds - with huge amounts of errors reported. I tried various settings as suggested on this forum and elsewhere but it was totally unstable. At one point the connection stayed up long enough to do a speedtest and it was very poor about half my usual rate and poor ping. Browsing was pretty much impossible. After half an hour I disconnected it because I didn't want my line being DLM'ed. It's now boxed up to go back. Surely the modem issues are not something that could be fixed with a firmware tweak it must be a hardware design or manufacturing fault to be that unstable.
 
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