Unlucky mate. Good luck with logitech support. I had a problem with mine (turns out it was interference with my old tft monitor strangely enough) but I didn't know that at the time and thought my unit was faulty. Rang Logitech support (barely spoke any English) and told me to take it up with the retailer.
After some arguing (and my lack of skill with getting my own way over the phone) I gave up and asked ocuk to have a look at it. They agreed to pick it up and have a look at it. A few days later it returned with no information, nothing.
There was no note, or email off them. I basically just got my speakers back in worse condition. There are dints and bumps all over my sub (which is more likely to be delivery damage) but on my speakers and control pod there are scratches and marks that weren't there before and the whole unit was wrapped in bubble wrap so I can't see how stuff gets scratches on them just by a bad delivery service.
Was not impressed by either ocuk or Logitech at this at all. First time I ever had to return anything to ocuk, but I just hope I don't have to return anything else. Was very disappointed since I've bought pretty much everything from ocuk.
Luckily it turned out to be a problem at my end so I did eventually figure out what was wrong.
I've had my 5500's for a long time now and dispite the bumps and the big dint in my sub's grill they still work perfectly fine.