XDJ-R1 has a background Hum or Fuz when a Microphone is active

I have an XDJ-R1 and I have noticed lately that when I have a wireless or wired microphone active and there is any low speech on the mic I can also hear a very audible background hum or fuzz sound.  When the speech stops on the microphone the hum or fuzz also stops.  I have tested the microphones on other mixers like a DJM 900 Nexus and a Behringer Xenyx 1202 and the hum / fuzz sound is not there.  So I have determined it is within the XDJ-R1.  I would like to know if any other owners of the XDJ-R1 also have this issue?