I have installed mythtv before, but I could never really get it to work properly with my Pinnacle PCTV TV card. I couldn’t record the sound from the tv shows because I had an old card. I finally found a post by someone named tcj that pointed me in the right direction. Basically since this is an old card I would need to use a jumper cable to catpure the sound from line in.

From: http://www.mythtv.org/pipermail/mythtv-users/2003-July/008852.html
“Pinnacle PCTV Pro. Video capture works using the bttv kernel driver. Audio
requires using a jumper to a sound card; btaudio does NOT work.” Note that btaudio is nolonger used as it was for OSS and OSS is now considered obsolete. ALSA is what you will need with snd_bt87x. Ubuntu 9.04 will automatically load the required modules: bttv and snd_bt87x.

Details on setting up the jumper settings for sounds here: http://www.mythtv.org/docs/mythtv-HOWTO-7.html.

You will first need to properly setup alsa. Do so with the following commands:
$ amixer set Master,0 100%,100% unmute
$ amixer set PCM,0 100%,100% unmute
$ amixer set Line,0 75%,75% mute captur
$ amixer set Capture,0 100%,100% captur
$ su
# alsactl store
# exit
$

Next, on the backend mythtv server set the audio capture device to /dev/dsp.

Change the output sound device in mythfrontend->setup->Audio from /dev/dsp to ALSA:default.

If it is still not working try this command to manually unmute your tv capture card:
v4lctl -c /dev/video0 setattr mute off