Video good. Audio shorted out?

[InsertHere]

I am having trouble with the audio on two PVR250MCE cards, and I am hoping for some help. I am using SageTV on a custom built PC running WinXP MCE 2005. Not intending to use MCE for TV purposes, only the other media capabilities.

The computer was built from scratch and installed XP MCE 2005 with the latest MCE drivers from Hauppauge. Using external cable box to tune channels. Everything worked fine, video and audio, etc. After about 10-20 minutes of TV running on the PC I get a loud chirpy noise followed by distorted sound whenever there is audio on the TV show. After about 20 minutes of the distorted audio the sound goes out completely. Now I am getting good video, but no audio at all on any channel. Resintalled drivers, changed slots, etc. No luck. I am using the Red/White composite input/outputs from the cable box to the pvr250.

When I use the same cable box and same input/outputs to a TV, audio is normal. When I take the cable box away and use the coax cable from the wall and tune with pvr250, I get audio and video through that cable normally.

I thought it might be the pvr250 card, so I shut the machine down and swapped the card with another which is exactly the same. Put it in the same slot, same drivers, etc. Same thing happened. Audio was fine, then chirped loudly, then distorted, now gone completely on all channels. Coax input works fine though.

I have a third and final pvr250 but I don't want to ruin that one too, if that is what is happening, so I have not installed it yet.

I then installed the two that failed into a totally different PC running WindowsXP Pro, and everything works fine but still no sound. Same result, only this time no chirps or distortion, just went straight to no sound on any channel.

Is it possible the audio components on the cards that control the composite inputs have been shorted out somehow? I am using pretty standard components, which I would think are considered good.
Here are the specs of the machine:
ASUS P4P800S-X motherboard, Intel chipset
P4 2.8GHz processor
1GB Kingston RAM
ATI Radeon 9550 video card
Hauppauge PVR-250MCE
300W power supply
Monster composite cable (also tried regular composite cable as well)

Any ideas?

[kny3twalker]

have you installed the newest drivers for the pvr 250s
and have you disabled MCE from starting with the computer?

[InsertHere]

Yes, installed latest drivers on both XP and MCE05 machines and MCE does not auto-start. Also tried the different settings under Audio in Sage to use different decoders, same result - nothing.

[kny3twalker]

MCE has background processes start with bootup
I could be wrong here but do not think so

have you tried installing winTV?

[InsertHere]

Getting same results on WinXP Pro as well, so MCE doesn't appear to be a factor.

I'll try WinTV tonight.

[kny3twalker]

if that does not work have you tried using coax input
so see if you can get sound at all
the card could be bad

[InsertHere]

Tried coax from cable box to card and get video but no audio. Coax straight from wall to card works fine for audio and video. Since the problem happened on 2 cards at right about the same run time (in same PC) I am wondering if there is something about how the cable box sends audio to the card that shorted out a portion of the cards' audio through those inputs, or possibly the cards are not compatible with the mobo?

Seems weird to me, but maybe the cable box is sending "unbalanced" instead of "balanced" audio, and that could overload the cards and blow a circuit? Still waiting for a reponse from Hauppauge tech support...