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bttv tv card audio inputs

I have an ATI TV Wonder with a bt878 chip on it. The video portion of the tuner on it died a while ago, so I have a VCR connected to the card via the composite inputs. The problem is when I switch inputs in the tv program (I've tried tvtime, xawtv and zapping), the audio is always coming from the tuner rather than the respective input. I found a few posts that had somewhat similar problems, but none of them had solutions that worked for me.

I've tried a number of different settings when modprobing bttv, including setting "audioall" and "audiomux" to various values. I enabled the gpio debug mode, started tvtime and then flipped through the inputs. The video source changed as it should, but the audio always remained on the tuner. After flipping through the inputs, I checked the output of dmesg:

Code:

[4300789.937000] bttv0: gpio: en=0000f03f, out=0000b03e in=00ff0fc0 [audio: off]

[4300790.308000] bttv0: gpio: en=0000f03f, out=0000b03f in=00ff0fc0 [audio: extern]

[4300803.824000] bttv0: gpio: en=0000f03f, out=0000b03f in=00ff0fc0 [audio: extern]

[4300804.791000] bttv0: gpio: en=0000f03f, out=0000b03e in=00ff0fc0 [audio: tuner]

[4300804.909000] bttv0: gpio: en=0000f03f, out=0000b03e in=00ff0fc0 [audio: off]

[4300805.349000] bttv0: gpio: en=0000f03f, out=0000b03e in=00ff0fc0 [audio: tuner]

[4300805.941000] bttv0: gpio: en=0000f03f, out=0000b03f in=00ff0fc0 [audio: extern]

[4300809.317000] bttv0: gpio: en=0000f03f, out=0000b03e in=00ff0fc0 [audio: off]

it looks like something changes when I switch inputs, but I have no idea if it switching to the proper values.

I've also tried setting different tuners, but that didn't work either.

I'm running out of ideas (though, being new to linux isn't really helping), so if anyone has any ideas, I'd really appreciate some help.

Thanks,
Deepak

Are you trying to say that using bt878 audio module does not change to composite. If so, try using the loop audio cable from the capture card to the sound card's line-in. Also did you forgot to plug the audio cable from the VCR to the capture card line-in.

Neither the bt878 module nor the actual output on the back of the capture card change the audio to the composite input. Everything is hooked up properly, as it works fine in Windows. Even if the VCR's audio wasn't hooked up to the the capture card when I switch to the composite input, I should get no sound rather than the sound from the tuner.

I haven't really done too much experimenting with the bt878 module. I figure I'd try to get the audio out on the card working before I moved on to that fancy stuff. The only thing I tried with it is piping the two dsp devices that it created to a wav file. When piped the analog one, no sound was recorded. When I piped the digital one, it recorded sound, but with the above problem of only recording the tuner even when the composite input is selected.

Thanks,
Deepak

I realized I forgot to mention this in either of my two previous posts, but I have some speakers plugged directly into the line out on the capture card, so I could eliminate the sound card as a potential source of problems.