hum using an active USB extender

[finnishcolumbia]

I am not a computer audio expert. But I have been using a USB DAC for a couple of years and have been very happy with the sound. Recently I moved my computer to a closet in the basement so I would not hear the fan. Now get a hum when I play music. I get it using winamp, windows media player, or pandora. The hum does not change if I adjust the volume. When I shut down the application, the hum disappears. Any ideas? Is there a better way to make a long USB connection? it's about 25 feet

[Erokhane]

Try wireless. Bluetooth maybe. Bluetooth can connect to USB.

 

Also check to see if the computer is next to any powerful electrical or radio sources. Make sure your current cable in good condition, contacts clean, and that the cable isn't bent or has anything too heavy on top of it. Make sure the computer isn't overheating and that the cable isn't near any heat sources.

 

I'm sure you know all that. But sometimes I forget the obvious.

[Skeptic]

This is almost certainly a ground loop because your audio equipment, the computer, and possibly the extender, will all be connected to different outlets.

 

Does your USB extension require a power source?

 

I have an unpowered extension from my PC going into a powered USB hub that is connected to the same outlet as the DAC, and it hasn't given me any trouble.

 

 

Something else to try might be an optical extender instead.

[4est]

Bingo!

This is almost certainly a ground loop because your audio equipment, the computer, and possibly the extender, will all be connected to different outlets.

 

Does your USB extension require a power source?

 

I have an unpowered extension from my PC going into a powered USB hub that is connected to the same outlet as the DAC, and it hasn't given me any trouble.

 

 

Something else to try might be an optical extender instead.