Weird noise in headphones when lid open

when my laptop lid is open there's a sort of buzz in my headphones but when i close the lid it goes :S

 

update ur drivers for sound. do a windows update

 

how would updating the sound drives do any difference? it's fine when the lids closed, i can even play music without hearing any problem also it's up to date anyway. same for windows update..

 

Hmm. Is it a high frequency of low frequency noise? The only thing that I can think of is possibly electrical noise coming from the power inverter that drives your screen.

 

it's a low pitch sound and atm i can't hear it at all but it happens every so often..

 

Does it come or go when the laptop is plugged versus running on battery?

 

Oh, it could also be background noise from your room if you've got a microphone on your laptop and it isn't muted. Also, make sure that the headphone cable is not near any other cables.

 

Maybe the processor is going into a higher c state when the lid closes, and thus the fan, which may be what's causing the EMI, spins more slowly. Or maybe some bus that runs close to the sound circuitry goes into a low power state.

Or maybe a piece of metal in the cover is changing the EM field when it's closed.

Maybe you can improve matters by setting more aggressive CPU throttling, or allowing a certain device to sleep when not in use. You'll have to experiment.

The best solution is probably to get a headphone DAC/AMP or other USB sound device. Turtle Beach makes some really tiny USB devices about the size of a large flash drive, and Headroom has the Total Bithead if you want something nicer.

 

lol, i didn't understand a word of that anyway i can live with it xD

 

If it is low frequency, then it is probably being caused by noisy power lines. The most likely source of electrical noise would be from your wall- see if the noise goes away when you unplug your laptop. If that doesn't make a difference, perhaps it is the inverter for your screen- actually, do you have an LED or CCFL backlit screen?

I really doubt it is the screen- what would make more sense is the microphone theory. Go into the settings for your sound card and make sure the microphone is muted.