Subwoofer making a random noise

[rodders]

Just randomly when watching things, the sub starts to output a rumble, doesn't seem to be linked to doing anything, just completely randomly. Not noticed it watching films on blu ray player yet, only when on TV feed.
Ages ago the auto on/off failed, so I just have the switch to on.

Bit awkward to know if it's the amp or the sub. Guess more likely the sub if the auto on/off had failed, maybe some other circuitry is failing?
It won't stop making the noise unless I turn it off then on, then it's ok.

Can't remember fully, but if I unplug the amp feed, it stops, can't remember if plugging it back in it starts again. I'll have to test again.

Don't have any spares to swap out and it's expensive to buy and hope! Lol

 

[rodders]

Oops, just did it....it stops and does not start again when plugging in.
But it seems to be quite frequent now.
I'll have to get a new cable and try that.
I was rummaging around the back of the amp and that seems to make it make a noise.

Will wiggle the cable and see if it does it more.

Don't have any other sources to put into the sub either, which makes it's awkward.

The only sources are ARC from TV and HDMI from blu ray player and they both do it.