Sony VAIO Z VPCZ11 Headphone Jack Static Noise

Is anyone else getting static noise from your speakers connected to the headphone jack on the VAIO Z VPC11?? I can't hear any static noise when using headphones. I have tried the earphones that came with the iPhone 3G then the iPhone 3GS and then a pair of shure earphones and the pair of noise cancelling headphones that came with the Z. All of them didn't have any static noise. But when I plug it into my LCD with built in speakers it have this constant high pitch static noise.

I thought it was my LCD's fault so I plugged in my iPhone 3GS and there wasn't any static noise. I did the same for my PSP and there wasn't any static noise. Also it did not have any problem when I was connecting it though the HDMI cable. Is the headphone jack really just meant for headphones? If so please advise me on what to do.

I want to connect both my PS3 and my laptop to my LCD which only have 1 HDMI port. So I bought a HDMI to DVI cable, which lead me to use the headphone jack for audio.

Plz help!

 

Perhaps your speakers work as microphones for noise cancelling headphones and feedback unto themselves thus amplifying room noise. Just go into sound properties and turn off noise cancelling function (on Enhancements tab of properties popup dialog).