bobguitkillerleft
Iv'e had very odd behaviour happen between tracks and busses,one of which is the before talked about phasiness,or polarity weirdness if using waves Kramer Tape on both a track and a buss simultaneously,which is now a big no no.
I just have the feeling that Sonar is packed to the gills with so much stuff,that sometimes odd things are just bound to happen,though I'm certainly only guessing on this.
I've had similar things happen when sending tracks to a bus with Waves Aphex on it, and also a dry bass track feeding a bus with a bass amp sim. But in my case, the phased sound would happen after the first iteration of a loop, and would continue until I closed the project and launched it again. I haven't seen it for ages though.