Denon 3312. Two years old. No issues up to now.
1) 3 HDMI inputs:
* Two DTV HR22 DVRs set to native output
* An Oppo 93 set to automatic output
2) 1 HDMI output into a 1080p Panasonic
3) Networking is not used/turned off (due to the reported fragility of the HDMI board)
4) Heat is not an issue.
1) One DVR had no picture, sound only. Did not work with 480i, 720p or 1080i output from the DVR.
2) Second DVR worked fine on all output resolutions.
3) Oppo only worked when set to 1080i output. Automatic output gave no picture; 1080p and 720p outputs gave a screen with garbage on the bottom third of the picture. 480p/i gave no picture.
Unplugged the Denon overnight (cold restart) and the problem was resolved.
Is this an indicator of more problems to come?
Had similar problem in the end it turned out to be a HDMI cable, as it is occurring on two inputs try swapping out the TV one.
I would have video then it would drop out leaving only the sound, i would then deselect the input and reselect input and video would start again, some good, some times every 15-20 minutes it would do this. Since the new HDMI cable has been fitted there has been nil issues