Look's like I've got a btaudio problem. I'm using a Hauppauge WinTV401 card and I can't get the sound right with btaudio. My audio is skipping and disrupting the video also.

I know it's not a weak CPU because the she's only running at 15-30% during live tv. But I have noticed that when I run the video without sound, and then load up the btaudio module and test it with sox, sox gives "buffer overflow" errors at about the same interval the audio was skipping. So I'm pretty sure they're related but I don't know enough about btaudio to figure it out.

Can anyone give me some insight into how to configure this? I'm afraid the patch cable isn't an option because I've got another 401 to put in when I get this one working and I don't have room for more sound cards.

Current btaudio module options:
options btaudio digital=1 analog=0 rate=32000 #who needs analog?
pre-install btaudio modprobe snd-pcm-oss #hand /dev/dsp0 to the mixer before loading

Setup:
chaintech 7NIF2 nforce2 mobo (onboard everything, APIC disabled)
AMD 2400+ 2GHz
2x Hauppauge WinTV401
512MB RAM
133MHz FSB, 166MHz RAM (could this be the bottleneck?)

Installation:
followed KnoppMythR4V4.1 auto install
installed i686-l package (no XvMC)
installed nvidia pacake

ps. Once I get the options right where's the best place to put them to make them load on startup?

Thank you, Myth Community!
-mike

Why not avoid the hassle of btaudio and just use a patch cable? Search the forum if you want to use btaudio.

_________________
cesman

When the source is open, the possibilities are endless!

I don't want to use the patch cable because I have 2 TV cards and not enough room in my case to add a second soundcard.

I've been searching the forums and googling like crazy. I'm the type of person who hates asking for help, but most of the btaudio info I've seen is people just throwing up their configs without explaining them at all. The config I posted is the result of that googling and the slightly increased understanding I gained from that. It kind of works, but it's not perfect yet. I was hoping someone could give me a rundown of what options are available for the module since the documentation doesn't, or maybe they see some obvious problem I'm missing. At this point I don't know what to take straight from someone else's config and what I would need to change for my own.

-mike

Ok I've narrowed my problem down a little bit. It was the analog audio that was regular pitch/time but with skips. The digital sound doesn't really skip, but it's way too slow and low pitched (like reverse chipmunk). I assumed before that that was the analog because of how the btaudio doc says the analog is something like ten times a normal digital sample. But it's the digital that's doing this.

sox -w -r 32000 -t ossdsp /dev/dsp1 -r 32000 -t ossdsp /dev/dsp
plays slow, low audio, with regular buffer overrun

Obviously there is a miscommunication somewhere. But damned if I know what it is. Any ideas?

After searching this forum, gossamer threads, and google. I can't find anyone else having this problem.

I have no direct solution for you, but the sound you describe could
be from a sampling rate mismatch.

Sounds like your playback is reading the sound data at a slower
sampling rate than it really is. This makes it sound slow,
and it causes the buffer to full up, which means that the software writing
the buffer eventually has to drop some of the audio stream.
That's the click sound you hear.

You'll have to learn how to set the sample rate for the hardward and
the software reading the hardware.. (Mythtv I guess in this case),
and how to get them in sync.

It sounds like you are close, like you are reading at someting like
40 khz, and your data is at 44.1k some cards also support 48khz

David