Whine in monitor speakers

[Baker Park]

I am getting a whine in my monitor speakers that seems to be related to my video card use. It persists even if monitor is turned off. Got worse with new Dell 30inch. Pulled USB cords to make sure it wasn't bleeding there. Also plugged in external USB Sound board and with no change. It will stop momentarily when I change window layout and then return. Thoughts???

 

[Egg Born Son]

Electrical fault. The monitor should not be capable of producing a sound if it is turned off (I assume you mean turned off at the monitor, not in software). If it still makes the sound with the power cord unplugged you have a ghost. As in paranormal.

Oh unless you mean your monitor screen. In that case it is still likely to be an electrical fault, a damaged cable or termination in the speaker. You can check if the source is the video card by removing it from you computer and seeing if that makes a difference. If you didn't install the card yourself get some help from someone who is familiar with the inside of a computer. Unplug at the WALL SOCKET before undertaking any work. A new monitor screen could easily result in the issue getting worse if the videocard is working harder to drive it. While you're at it check the videocard physically and clean any dust out of the heatsinks and fans.

Check the integrity of all cabling and connections. This means running your fingers along the entire length of the cable feeling for bumps and lumps, kinks etc. Like checking your ball/breasts for cancer. Check all connector plugs and sockets for damaged pins and make sure they are all firmly engaged.

If the cables and connections are in good condition and the internal circuitry in the speaker box is okay (don't open the speaker box, the fact you're asking this question suggests there's nothing you are qualified to do in there) the other possibility is that RF interference is getting in through your power supply. The noise from a faulty videocard could be backfeeding into the power supply from the wall and bypassing your speakers shielding by getting in through the mains power cable. I encounter this every other day with faulty consumer goods in my line of work. RF interference and AC coexist perfectly happily but consumer goods don't like it! The test for this is fairly simple, you need to plug monitor speakers into a different power circuit to the computer. Odds are your washing machine is on a different circuit so first try running an extension cord from the washing machine to your monitor speaker. If this makes it go away you need a new videocard.

If none of this gets you anywhere, time to get a guy in or take it to the shop for testing. There are too many ways to get hurt if you don't know what you're doing.

 

[Baker Park]

Thank you for the time you put in to this. I have a temp fix but not sure why it is working. I put in a ground fault lift on both channels between the sound out and the mixer which quieted it all down. Where might you think the cross might be happening? Am going to follow your lead when this project is off the drives and clean house.

... one again your thoughtfulness is appreciated.

Best

 

[Egg Born Son]

If a ground lift worked then it is likely a cable to blame, probably the shielding or even a poor termination in the plug. The less likely possibility is that videocard or mixer has an electrical fault and has found a second path to earth somehow. You only want one reference ground, electricity and RF signals should never be given options, they like discipline. If all your power plugs are 3-pin and they are all plugged into the same household circuit then equipment fault is a possibility.