HDMI sound problem

I'm having a problem with the HDMI connection from my laptop to my high def TV.

I have a DELL Inspiron 1525 laptop connected to a high def TV via the HDMI port

If I boot the machine using Windows XP Pro (which is what I have installed on the internal drive), the picture shows on the TV and the sound come out of the speakers on the TV.

But if I boot Knoppix (which I run from a 4GB Kingston Flashdrive), the picture shows on the TV but the sound still comes from the laptop (rather then from the speakers on the TV)

Most people are going to say "why not just use XP"

The answer to that is: When I use XP (to watch TV on the Internet), every so often the show (playing at the time) runs in... kind of slow motion. Its almost like the processor is having a problem rendering the picture.
It doesn't occur very long and it always speeds-up again but its very irritating.

When I run Knoppix, this problem never occurs (ie. The TV show plays smoothly all the way through)
But again, the sound continues to come from the laptop speakers (rather then the speakers on the TV)

This is something I have never tried before but maybe the problem should be divided as two,

1. To identify if the system has identified the presence of audio on HDMI
2. To channel the voice to the right audio device

For (1), you can try this command 'aplay -l' to see if there is 'HDMI' audio
For (2), you need to run 'alsamixer' and/or 'amixer' to channel the audio to the HDMI.

I think that you should create a configuration file /home/knoppix/.asoundrc as described in the thread http://www.knoppix.net/forum/threads...l=1#post121157

If you want to use more than one audio device at a time then you should install pulse audio. It allows you to select the audio device in a comfortable way.