Audio Systems: Behringer audio mixer--sound only coming from left channel, mixer sound, light timer

Question
Dan, I have an unusual problem that I suspect has to do with the electrical current in my apt.  The problem is with my Behringer Eurorack UB502 mixer--sound is only coming from the left channel.  I've tried multiple plugs, panning left and right, etc. but no sound from the right channel.  The mixer used to work in my apt., and now it doesn't.   Thinking my mixer was broken, I bought a new Behringer--but the same problem happened!  I tried plugging in the old mixer at work and yes it does work from both channels!  So there must be some weird problem in my apt. with the current--maybe there's not enough power to reach the right channel?  I've tried nearly all the outlets in my apt. but I can't get sound from the right channel.  All of my other electronics equipment works fine, including a Yamaha keyboard with monitored speakers and a home theater system and desktop computer, etc. -- except once a brand-new light-timer switch (the kind you use to automatically turn on a lamp when you go on vacation) wouldn't work for me, which I thought was strange.   The power on the Behringer cord says 115V 60Hz 105mA 12W.  I've tried plugging it directly into numerous outlets as well as using some (low-cost, kind of basic) surge protectors that I have.  Any ideas?  Are there any adapters or advanced surge protectors that might alleviate this problem?  Any help would be appreciated.  Thanks, Mark

Answer
Well, this is a new one on me!!  The only possible explanation is that the unit internally uses B+ and B- voltages.  It is possible that you have a wiring problem in the house where your neutral is floating.  You may have lost the central stability of the power supply.  Check your outlets to see if you actually have a valid neutral connection.  Measure between the hot and ground, then the hot and neutral both should read 110V.  I suspect that you will read 0 between hot and neutral.
Keep us posted.
Dan