Ubuntu creeps when video is played

[encyclopedia]

Hi Friends,

I am new to Linux. I started by installing Ubuntu hardy x64 three days back. I have an AMD x64 dual core processor.
I am bothered about two things though.

1. I have a Creative 4.1 surround sound speaker system. When I play music in ubuntu, the music plays in only two channels. The sub-woofer and the rear channels are muted. This is a serious concern for me since I am a music freak.

2. Also, when I try to play video (through totem player - Ubuntu's default player) and also VLC, my computer becomes dangerously slow. I don't know whether this is some configuration problem or what but this is a BIG problem for me.

Apart from the above two glitches, Ubuntu Rocks. I am sure there is some setting or drivers or configuration out there but I am not able to figure them out currently in the internet. So I am reaching out for your help.

Thank you.