Yeah, me too, maybe not so much "out there" but at least for volume, filter sweeps, that sort of thing. All worked perfectly until this one. I'm just sure if it's a Breverb thing or a glitch with Sonar X2, or what.
FWIW, I just did a workaround by splitting the clip, fx on the clip, then cross-fade, but it's more flexible with the envelopes.
I ran a re-install of X2 the other day (for various other reasons too) and it still behaved strangely.
Thanks for looking into it, Craig.