I have the Bose C5 Multimedia sound system. Whenever I play a video from the internet, my sound cuts out. I cannot get sound on any program until I reboot. I hear a buzzing sound why the PC starts up and then it works until it cuts out again after a few minutes of watching a video.

How can I fix this?

Thank you for your help.

Audio Players & Recorders - Bose - Companion 5 Multimedia Speaker System (3-Piece)