Korg Forums

[yaseedee]

Hi everyone.
i bought my new microX just before xmas.i love it but when i use usb connector all the outputs of the micoX produces low level noise and as it seems to to me it seems like it is the sound the internal machine of the computer coming out from the outputs.But headphones output is ok.
what's happening did anybody had such problem?
Thank you all guys for help.

[xmlguy]

You might be experiencing a "ground loop" problem. This occurs when there is a voltage difference between the electrical ground of two or more different devices attached to each other, causing an electrical flow between them through the ground attachment of any wires that connect them. The most common symptom of a ground loop is a 60/50 Hz hum, but sometimes electrical noise similar to what you describe is a symptom too.

One common cause is when the devices are connected to two different wall plugs in which there is a voltage difference due to differences in the wiring back to the building circuit breaker. This can be solved by hooking the devices to a power strip from the same wall plug.

More complex is when the power supply of one device causes its chassis to float with a voltage above or below the wall plug ground, often due to a failed component or a bad internal connection to the A/C plug ground. You can use a multimeter to check for a voltage between the chassis and the wall plug ground. You can also check the voltage between the chassis of two devices when they are _not_ hooked together with a cable between them. PC power supplies are notorious for poor construction and bad filtering for audio devices. Sometimes the solution is to get a quality power supply.

Be careful however, because a shock hazard could exist when a ground loop condition exists. I've personally experienced shocks as a soundman for live gigs due to ground loops.

[yaseedee]

thanks a lot i will go to try.......

[Clauzii]

For some odd reason, everytime I change sounds, the microX PSU itself(!) sends out a whining noise. It works, but annoying none the less

[yaseedee]

Well my problem is different but thanks anyway for the information .i think that xmlguy is right but unfortunately i couldnt check it yet.

[Clauzii]