I've had a Denon 890 for 11 months with no absolutely problems. In the last week, however, on several occasions it has shut down with flashing red standby button. Turning it off and back on brought it back to life each time. It's in a cabinet with plenty of space, temperature was not hot, speaker volume was not high. A chat with Denon tech support brought up, bad HDMI cables, speaker impedance, power strips, etc. But the fact remains that nothing in my system has changed in the past 11 months. Does it sound like the unit is going bad? Thanks.