Problems with Jack, headphones not recognized

[SixFingers]

I try to start Jack off the A/V Linux Live Cd and I get:

ALSA: Cannot open PCM device alsa_pcm for playback. Falling back to capture-only mode
cannot load driver module alsa

What is the PCM device? Does this have to do with why sound isn't coming through my headphones? Ubuntu doesn't recognize the headphones either, but Mepis does. I also have no problem starting Jack with Mepis.

[studio32]

I doubt if AVLinux is meant to use as a live-dvd (not sure)

I suggest you to start with reading the wiki: http://wiki.linuxmusicians.com/doku.php?id=newbies
especially the Jack info..