Most likely some badly shielded analog path in your PC is acting like an antenna, picking up USB or PS/2 signals.

Do you have front panel audio hooked up? Try disconnecting it. Also check that all inputs are muted in the mixer. Are you exclusively using the SBLive or also onboard audio?

dionb wrote on 2024-11-08, 10:38:

Most likely some badly shielded analog path in your PC is acting like an antenna, picking up USB or PS/2 signals.

Do you have front panel audio hooked up? Try disconnecting it. Also check that all inputs are muted in the mixer. Are you exclusively using the SBLive or also onboard audio?

No fornt panel, onboard audio disabled in BIOS, DVD ROM audio routed to the analog CD In socket on the SB Live, all inputs otherwise muted in the Windows sound mixer. The mouse is a Cherry optical model running through a USB to PS/2 adapter.

Does it only happen when you drag windows around and not when you only move the mouse around?

Could be marginal power quality causing modulation, as more power is drawn when moving stuff around on screen. The noise might even come from ground, as higher currents can shift the ground level around too.

st31276a wrote on 2024-11-08, 10:44:

Does it only happen when you drag windows around and not when you only move the mouse around?

It's only when I move the windows around, i.e. when I grab the title bar and drag it around, yes.

My guess is it is the graphics card drawing power in bursts, every time a ps2 packet arrives some on screen work is done rather quickly, hence the changing of the note at changed ps2 rates.

Maybe worth a try to see if the noise is quieter if the sound card is in a farther away slot, also test onboard audio to see if problem is there too.

Might be a filtering issue, caps on power rails on motherboard.

st31276a wrote on 2024-11-08, 10:44:

Could be marginal power quality causing modulation, as more power is drawn when moving stuff around on screen. The noise might even come from ground, as higher currents can shift the ground level around too.

It is a "interesting" problem .. a test might to be running something that does serious processing (like a performance test) which
should make the system draw a bit more power - see of the symptoms change with more power draw

Dave ::: https://dunfield.themindfactory.com ::: "Daves Old Computers"->Personal

Oddly enough, I can hear this buzz even if I select "Mute All" in the Windows sound mixer.

revolstar wrote on 2024-11-08, 12:54:

Oddly enough, I can hear this buzz even if I select "Mute All" in the Windows sound mixer.

Its not an audio signal. Its likely being carried by the ground.

CRT? ..... 'coz that's the only time I had something similar, about 1997 in max res on a vlb system with GD-5429, and I'd get a buzz moving windows, dragging icons or scrolling, when the speakers or cord were too near the monitor... keeping everything 8" away it didn't happen.

BitWrangler wrote on 2024-11-08, 13:39:

CRT? .....

Indeed! A Flatron 774FT

OK, I've tried the AC97 on-board audio and there's no buzzing.

Maybe it's due to your cd analog audio cable?

That's most probably a ground loop type problem and it can happen due to CD audio cable or PC speaker connection if present. Sometimes the problems leaks in from +12V line and is an indication of bad capacitors on the analog supply rails of the sound card.

revolstar wrote on 2024-11-08, 13:54:

OK, I've tried the AC97 on-board audio and there's no buzzing.

Ironically it would have usually been the sound card integrated to the motherboard that would suffer things like loud hiss, buzzes, clicks and other interference from the other components inside your box.

Does swapping sound cards (or slots) make a difference? Maybe moving the card to another slot is enough to correct the problem.

Try a shielded audio cable

Also, use an outlet tester to make sure the ground on the outlet is actually there.

'Floating' ground is *infamous* for causing this issue.

Thanks for the suggestions peeps. I've swapped the slots on the MoBo, removed the analog CD audio cable - the buzz is still there. I'm considering getting a different Sound Blaster.

Have you checked the earthing/grounding? If that's the cause, a different card won't make a difference. Would be a shame to throw money at the problem before being sure.

dionb wrote on 2024-11-09, 10:11:

Have you checked the earthing/grounding? If that's the cause, a different card won't make a difference. Would be a shame to throw money at the problem before being sure.

Aye, I've checked the grounding points on the card, they seem ok.