Twelve months ago I bought a Denon AVR-2803 AV receiver and Acoustic Energy Evo speakers. After 10 months of use, I noticed that the sound was distorted in the front left and right speakers when playing DTS DVDs and CDs. It's not there straightaway, and typically starts about 30 minutes after playback is started. Once it's there, there's no way to get rid of it. Dolby Digital and PCM work OK. I've tried two DVD players - Toshiba SD340E and Daewoo 5800. I'm using a coaxial cable between the DVD player and 2803. I returned the unit to my dealer and after five weeks eventually got it back. Their report says, "unit tested and no fault found." However, it still has the same fault. I've disconnected everything apart from the front speakers and DVD player and still get the problem. I've even turned off everything in the house just in case it was some kind of weird interference. I've worked in pro audio for 20 years, and write instruction manuals for various Japanese audio manufacturers so I know a thing or two about distortion. However, this problem has got me stumped. Any ideas would be greatly appreciated.