Radio/ CD stopped working

My radio and cd suddenly stopped working.
Drove in the evening everything was fine, turned on the car in the morning and power button doesn't turn on radio; voice, mode, volume, handsfree buttons, don't work.
My navigation works fine with voice. I can still call but have to dial through my cell phone.
None of the light on radio/cd work.
I checked fuses and they are all good.
Anybody have any suggestions ideas?
thank you.

 

I did search, but could not find anything.
It's like I have no power going to the radio.
I wonder if it got disconnected on the back.

 

I looked at the manual and check all the fuses related to "audio system"
Even replaced the main "audio system" fuse, I think number 45 or 46, with a new one, but no go. Unless there is a possibility that other fuses not marked with "audio system" in their description can cause radio not to work.
I wonder if it's possible that cables in the back of the radio come undone?
But the way they fit it is probably very low possibility.

 

Today, after work, got into my car and radio is working!
One thing I didn't mention is that I went to Tahoe over the weekend. When I was driving there the radio was working. I spent 2 days in Tahoe and on the way home, my radio stopped working. It was pretty cold there.
Could it be that the cold or altitude affected something and the radio lost power, and then two days later it went back to normal?