[mythtv-users] BT878 sound quality

[Adam Felson]

I have two video capture cards, a BT848 based card and a BT878 based
one.

I now have the BT848 one running like a champ, with it's sound output
running in my asus a7v333 motherboard's onboard sound.  Before I got the
848 running, I first tried the 878 and I couldn't get decent sound.

With it's sound output running into a sound card, I get a metallic tinny
sound.  It isn't clipping but sounds like some kind of resampling
distortion.

I tried the OSS btaudio driver on the 878.  I use the following insmod
command in my rc.local: insmod btaudio dsp1=2 dsp2=3 mixer=2 rate=32000 
I've verified that it is really creating the /dev/dsp devices;  I can
have it create /dev/dsp4&/dev/dsp5 if I want.  On the first dsp, I get
absolute silence.  On the second dsp I get some kind of digital noise
like running an s/pdif output into an analog input.

I then compiled alsa version 1.03 and tried it's bt87x driver but I
can't get any tv audio on that either.  It's mixer is very simple, just
a capture selection for tvaudio or radio, and a single capture level
adjustment set to 100%.

Anybody have any luck with bt878 audio?

-- 
Adam Felson <a.f.5 at pobox.com>