Sound on my laptop randomly lowers

[kjtoshiba]

as i am surfing the net im lstening to musc on my toshiba satelittle laptop, running vista 32bit, 2gb ram, 160gb hd. the sound automatically will lower from 5 down to 2, then from 2 - 0 without the touc of a button?

 

[joytime360]

That's quit strange, heard never heard about this kind of problem.

 

[joytime360]

Is there any virus on your laptop?? Hope not.