wannafish said:
i thought i would wait for replys but let me add this- the problem went away when i put all existing circuits on the same phase. any more thoughts?
warning, stream of consciousness follows...
Dropped or loose neutral? maybe not though, because putting them on the same phase I would expect them to just stop working all together if that were the case.
Had a 2 circuit track once with a similar problem. Hooked up to dimmers, each circuit happened to be on a different phase. Couldn't figure out why this track was always dimmer than other tracks on the same circuit. Turns out the contractor did a poor termination job and the neutral was just hanging loose. because the track was a shared neutral, we actually ended up with 2 circuits for and fixtures designed for 120v in series and fed with 208. Because it was being fed from dimmers anyways, voltage readings were not an obvious indicator of a problem. One of the tests that led us in the right direction was that turning off either circuit breaker turned off both circuits of the track, but turning the dimmers all the way down did not because these units did not have air-gap circuitry.
While this is not the same scenario you are working in, there might be some similarities.