Sounds like a ground loop. Switch the polarity, if you can. Or use a 3-prong to 2-prong converter for your AC plug.
On Wed, Apr 8, 2015 at 7:25 AM, M M strategy400@... [gsp-2101] <gsp-2101@yahoogroups.com> wrote:
Hi, this isn't really a 2101 problem, but I had a problem at last band rehearsal and wondering if anyone can suggest a solution. I had plugged my 2101 1/4 inch outs into my amp (Marshall s80) and then the XLRs into a Mackie board/PA. All was well (quiet) until my bandmate plugged his keyboard rig in, at which point my amp started making a LOUD buzzing noise. I had him unplug the keyboard rig from the mixer, the buzzing remained. I unplugged the 2101 from the mixer, the buzzing ceased. I think the buzzing was coming from/through the power circuit to the room, which all the items shared (mixer, keyboards, 2101, amp etc.). I ended up just playing through the amp and not plugging into the mixer, but for performance there will be a need to run through a FOH system at some point.
Would a power conditioner, like a furman unit fix this issue? I'll likely try this at next rehearsal.