Speaker buzzing

Well, the sound has happened for a while, I'm not sure if it made that noise from the beginning or not.

rayford52 said:

I just joined so I hope I am not putting this in the wrong thread...my problem is, when I plug in the mic on this computer I get a buzzing from them,, and the higher I push the mic, control and mike boost the louder it gets. I have tried different speakers an a different mic. still does it.. I even ran an extension cord from another electrical outlet and it still does it.. I am su

Hello and welcome Rayford mate best start new threads when you have problems as it can at times cause confusion on who is answering what and who

Anyway it does appear to me that if different speakers and/or microphone are being used and the noise is still there then there is possibly a problem with the socket contacts and/or the soldered joints for the socket to the motherboard or if the connections are in the front of the machine maybe the audio plug / socket header on the board itself.

That's o mate you just need one of those very bright LED torches to see inside the sockets and perhaps a magnifying glass - it could even be just down to wear and tear. I meant to mention to when looking at the header/s on the motherboard just check to see if the thing rocks slightly - may indicate a dry joint (solders come undone) and look for and caps that look suspect and any signs of scorching on the PCB

Hmm sorry we couldn't get it fixed right away. It probably is something really quite simple but while I am thinking about it the buzzing is it around mains power supply frequency - usually around 50Hz? because a fault in the grounding system could possibly be another cause of the problem.
Just check that the motherboard is firmly grounded and the easiest way of doing that is to measure the resistance between the case, motherboard fixing screws, black leads on the 24 pin power plug and the third earth pin on the mains power lead. All you need is to unplug the power supply to get to the plugs' earth pin and use a (preferably) digital multimeter and set it to resistance and when you touch the mains earth pin and any of those connections I spoke of there should be a zero resistance. If there is resistance then something is quite wrong and could be the cause of the humming sound because a good ground connection usually stops any extraneous background mains hum from happening.

Not really mate in fact that may even make another one if indeed a ground loop is what it is. A ground loop is best described here https://en.wikipedia.org/wiki/Ground_loop_(electricity) < if you look at Sources of ground current there are some simplistic pics and explanations of ground loops.

I used to tinker a lot with audio stuff in the past and especially with vacuum tubes and ground loops were always a problem especially with equipment that was plugged into an amplifier say phones speakers mikes etc etc I spent many an hour wiring grounds to those things so that there was only ever one ground point - typically at the incoming mains ground source. So in a nutshell you would be chasing ghosts.