Audio Systems: Sony STR-DG710 sound problem, auto calibration, tv amp

Question
Before I start, please know that I am a total novice at this and will do my best to describe the problem but I will not be using very technical terms.  I have a Sony STR-DG710 receiver and it's hooked up to my TV via Video 2 and my cable also runs into my DVD burner via Video 1.  I was watching TV on video 2 today and in the middle of something the sound just cut out.  The speaker formation in the left corner of the screen is gone and there's no sound.  When I switch over to video 1, I see the speaker configuration there but there is still no sound.  I unplugged and replugged my HDMI cables and I reset the receiver to default settings and still no sound.  I don't even know how to trouble shoot this.  Once before I had the sound cut out and I did a bunch of things to see what the problem was - I got it to work again by going into Amp menu, 6-Video, HDMI audio and changed the setting to TV + Amp.  That worked, but I don't know why - but from then on it always said PCM 48 on the display and it doesn't anymore (I sense this is the root of the problem but no idea what to do).  I did and Auto Calibration and there were no errors.  I did a tone test and the speakers are all fine - sound comes out of them for all the tests.  But no sound with my video on those settings.  The sound DOES work on SAT and Tuner settings - it's worth mentioning that SAT is the component that runs from the receiver to the component (Wii) with no HDMI cable, so I wonder if there is a faulty HDMI cable somewhere?  I tried to do all the things the manual suggested to trouble shoot to no avail.  Any suggestions on what to try next would be appreciated.

Answer
You could try an HDMI cable, but if you are still getting a picture, I doubt that it's a bad cable (with HDMI - the video & audio are embedded together in the bit stream that travels through the cable. If you lose one, you lose the other)

If you could be more specific about the gear you have plugged into the receiver (brand and model #) it may help. If you can include HOW they are connected (hdmi, component video, composite video, etc...)

With this info, I can probably locate the owner's manuals and suggest some troubleshooting steps that the manuals leave out.

Thanks