Volume turns down? Please help.

Yes, My Volume turns down when i open up GMOD and join a server, It turns down the volume of GMOD, Around 15% or 20% or something, so i can barely hear it…This has been happening waaaay before the recent updates, But I finally found time to post this help up, Why is this doing this? how can I fix it?

So Basically, I just join a server, And the volume turns down by itself, I have to alt-tab out, Turn it back up, Sometimes I even crash, It’s extremely Annoying, Please help.

First of all right click on the sound icon in the taskbar and hit sounds.

http://dl.dropbox.com/u/8165303/rightclick.png

Then click the communications tab and tick do nothing.

http://dl.dropbox.com/u/8165303/communications.png

Awesome bro, It fixed it thanks alot.

No problem.

How do I do that on windows vista?

Should be the same.