Sound output goes down when I open Counter-Strike

[georgek7]

Whenever I'm listening to music and then I open counter strike, the sound output of my computer goes down dramatically. The max volume is as loud as my normal volume would be. I have windows 7.

In game I turned all the sounds off, but I still have this problem.

Does anyone know why?

Thanks in advance

 

[Tmagic650]

Have you updated the video cards drivers or checked for a resource conflict (any yellow exclamation marks) in the Device Manager?