I've got Zephyroth 10.5.2 up and running, everything works except the sound. Whenever I try to listen to sound (say, when visiting a youtube page) I can here a small burst of sound, but then it stops. It plays the first second of sound correctly, but after that, it's just silence (and no, it's not the youtube page to blame, I've checked it multiple times). I have no idea why this is happening, can someone please help me?

Specifications:
AMD 3200+
ASUS A8V-MX K8M800 MOBO
GeForce 7600 GS 256MB AGP
Realtek ALC653 on-board sound