Alex Tinsley wrote:
First off any noise that you hear through your USB Audio interface is because the grounding in the audio device is using the grounding on the laptop which is most commonly data ground wired to earth ground. So you hear all computer noise through the audio output. One way to alleviate this is to lift the ground on the laptop (unplug the power adapter from the laptop or get a ground lift adapter). Noise goes away. A lot of devices suffer from this, 1394 has same issue.
I only get noise on my USB soundcard when I plug it into my external hub. I get no noise with it plugged directly into the laptop. I guess the laptop ground is OK and the external hub's ground is junk.
The hub has other devices plugged into it, I don't recall if I tried using it with only the soundcard. Wouldn't be surprised if some of the other USB devices on the hub (scanner, printer, MIDI interface, PS/2<>USB adapter for keyboard & mouse, flash card reader) are sources of noise by themselves.
Thanks for the extensive info! -- David gnome@xxxxxxxxxxxxx authenticity, honesty, community _______________________________________________ Linux-audio-user mailing list Linux-audio-user@xxxxxxxxxxxxxxxxxxxx http://lists.linuxaudio.org/listinfo/linux-audio-user
