No sound on my Sony PCG-TR1 Centrino

I am using the latest version of Knoppix CD.

I boot from the CD with cheat code alsa. Info Center of KDE shows :-

Sound Driver:3.8.1a-980706 (ALSA v0.9.2 emulation code)
Kernel: Linux Knoppix 2.2.21-xfs #1 Fre Jul 25 00:06:47 CEST 2003 i686
Config options: 0

Installed drivers:
Type 10: ALSA emulation

Card config:
Intel 82801DB-ICH4 at 0xe0100c00, irq 9

Audio devices:
0: Intel 82801DB-ICH4 (DUPLEX)

Synth devices: NOT ENABLED IN CONFIG

Midi devices: NOT ENABLED IN CONFIG

Timers:
7: system timer

Mixers:
0: Analog Devices id 74

But I cannot hear the sound from my computer. So, I set the "Sound & Multimedia" in KDE Control Center. Sound system -> aRTs -> enabled "Start aRts soundserver on KDE starup". Then, Sound I/O -> selected "Advanced Linux Sound Architecture" at Sound I/O method. Enable full duplex operation. Set 48000 at sampling rate. When I save the setting, I get the following error message :

Error while initializing the sound driver:
device: default can't be opened for playback (Device or resource busy)
The sound server will continue, using the null output device.

How can I solve this problem? Thanks.

Also, xmms will hang anyway.