DENON AVP - a1HDCi - HDMI board issues - Surround Sound

I have noticed that when I turn on my Denon AVP i.e. “cold start” I have little to no center channel sound and the left channels are significantly louder than right channels.

Then voila, after 15 to 30 minutes of “warm up” unit sounds amazing - as it should.

I did tons of research on other forums and seems other’s had same issues with HDMI boards.

However, DENON - terrible support - don’t have replacement boards and most electronic shops won’t touch unit.  Very complex, state of the art (but older) 60 pound unit.

Does anyone here have knowledge, experience and solutions to this issue?

Once get the ball rolling I am adept enough to take out boards and take pictures, etc.