Processor end. "Ground End" (most likely) refers to the end that the "floating shield" is connected to the ground ring of the RCA plug, and is the end that should connect to the preamp or processor.
Also, if you experience noise or hum, lifte all component's ground pins at the AC plugs using cheater plugs and only allow the pramp/processor to be "grounded" at the wall.
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Also, if you experience noise or hum, lifte all component's ground pins at the AC plugs using cheater plugs and only allow the pramp/processor to be "grounded" at the wall.
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