For testing purposes, take the cover off your denon, get a hairdryer, find the dts chip on your hdmi board.  Get the chip hot enough to have expanded and turn on the unit.  If it comes up you have a solder issue.  It will stop working again when the chip cools.  You could fix it.  Hot air gun, flux, thermal paste, heatsink.  I have done this to 4 receivers from this era and it worked.  It's on YouTube.  50 bucks for a fix or buy new.