Noise problems with Diablo 2

[Jimmy 2004]

Ok, I know its an old game, but I've only just got it and would like to play it without extra sound effects. The problem is that now, every time I play Diablo 2, whenever my character is standing still, there will be a high pitched murmour in the background. Whenever I begin moving my character, the noise will stop until the character becomes still again. This wasn't happening the first few days, and it does seem to be a new problem. The most strange thing is, my PC is running demanding games like Half Life 2, Call of Duty and so on with no problems. The sound isn't coming from the hard drive, or the PSU, and it isn't coming from the CPU or GPU fan, and at the moment I have no other fans. I believe the sound is most likely coming from either the CPU or graphics card, or the motherboard area in between those two. I have an Asus K8N motherboard, and all my main specs are in my signature. I have tried running Prime95 with no sound problems.

I know this probably should be in the games forums, but I know it must be hardware making the noise (no, it isn't my speakers or any other external device) and I would appreciate any help

Thanks

[Anarion]

i have some of these noise * pitch for my own too , like; sometimes when run atitool ,some dos ,dvd player , they come & go & i done whatever u say but they are still goin on ;D....& it's from MNT sometimes (almost) & then some time from within case !