Thanks for replying. More details are in your PM box. Yes, it's pretty much just the Plexi models. I'm not running anything in the loop save a Planet Waves patch cable to allow it to act as a solo boost.
I've not heard the phasing on anything outside the Plexi Models save the DC Vintage OD (which is HAWT). it's got the plexi preamp though, which may account for why there's some phasing there too.
it's just weird. Seems to be more a part of the low end than the higher strings... unless i give them a good shake. Vibrato seems to bring out the phasing a bit.
Mostly, i want to make sure I'm not just hearing things!