Greetings!

odd thing is that as i turn the gain down on the amp, the noise gets worse

Definately a ground loop. And, from the sound of the above, it sounds like it is running through your signal lines (did you turn up the empeg to compensate for the lower amp?). You can try filters in your signal path, or reconnect / check your grounds at both the empeg and the amp.
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Paul Grzelak
200GB with 48MB RAM, Illuminated Buttons and Digital Outputs