Ground lifting the power source 'plug' can also be beneficial to eliminate hum and buzz in a Sound Sytem. "Ground lifting takes a 3 prong 'cord' and using a simple gound lift - 3 prong - (from Device) to 2 prong -(into wall outlet) adapter."

Best regards,
Mike
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Yamaha Genos, Mackie HR824 MKII Studio Monitors, Mackie 1202 VLZ Pro Mixer (made in USA), Cakewalk Sonar Platinum, Shure SM58 vocal mic.