Acer 5920 - High Pitch noise on increasing volume

Hi everyone.

I was using my 5920 yesterday and when i increased the volume of the speakers with the help of the wheel under the touchpad, there was a loud high pitched feedback type noise from the speakers. I decreased the volume and it was back to normal. When I again increased the volume, the high pitch noise again came from speakers.

I tried restarting the system and also the reinstalled the driver but the problem still persisted.

Also, the noise comes when I increase the volume above 50% even if I am not using the speakers for hearing anything at that moment. The strange part is if I use VLC Media Player and then increase the volume to its full it doesn't give the noise but when I try to increase with the help of the wheel in front of the laptop (or for that matter from the volume mixer also) it gives the noise. Also, when I try to close the lid, this problem occurs at a lower volume.

What could be the problem here?
Can anyone help me out?
I'd be very grateful if anyone could shed some light on this strange problem or perhaps put forth some ideas. I've come here first because i don't particularly want to send it back to acer unless there is no other option.

Thanks for your help in anticipation.
Kinnu

 

Reset your sound settings(I think problem is your mic output volume).I got same kind of problem (Hi sound when closing the lid)while ago after I change my mic settings.