I tried to play a Guitar Pro file with TuxGuitar (installed from Add/Remove Software function, Ubuntu 9.10) and the program completely cuts all sound from the system, including the other applications. The main problem I'm having is that the sound problem has spread to my other OSes (I triple-boot with Windows XP and Windows Vista) and sound won't play from any of them. This being the case, I think this is a hardware error. I have no idea how to fix it however. Any suggestions?