Sound Messed Up?

I cannot for some reason here speech in my songs, the speech seems quiter and my sounds have gone weird, like my footsteps get louder and quieter in Counter Strike: Source, I have the Realtek HD Audio Manager and no other sounds software, can anybody help me sort this out?

Very strange, a mate of mine had exactly the same problem the other day.

Couple of things to try:

A. Make sure your speaker 3.5mm plug are 100% pushed into your sound card
B. Test your speakers on another computer if you can
C. Reinstall your Sound Card drivers, try and find the latest one possible

Not sure how my mate fixed his, but I imagine it's a pretty basic problem.