Over on AVS a few users with x09 series Onkyo AVRs, specifically 709 and 3009 so far, have commented that since doing the December 2011 FW update, their sound has, and I quote, "started to resemble a cheap AM radio". The users have repeated their (previously good) Audyssey calibrations and have found the same result. However, on switching to the MUSIC curve, their former listening glory has returned. In the absence of any other changes, it would seem to point to something in the FW update that is causing the problem. Given that Onkyo have had issues with FW updates in the past, do you know of any recent FW changes that could cause the described effect, and why would switching to the Music curve fix it?
I will be updating the FW on my own 5509 soon so that I can use the Pro kit I have on order and I would hate to think there is a bug. Any comments gratefully received, as always. Thanks, Keith