I have a Yamaha mixing board, recently aquired, and a Graphite iMac. The headphone out crackles when I wish to use it as an audio return. And the iMic hummmms. I have connected the iMac and Mixer to the same power source (AC outlet) and still the same problem. If the iMic or headphone out is instead lead to a pair of Headphones, the humming and or crackling does not exist. Is this my computer, or my mixer?

iMic is plugged into one of the two USB slots, not hub. I am looking at an Edirol USB capture. But other postings indicated that it's USB related and won't be solved by a different device.

I have a Firewire DAZZLE video bridge, but I don't think that can be used as an audio capture. Any help is welcome.

Mixolidean