Beepster
The project I have open doesn't have a MIDI track. What are you seeing?
I think they should have named that knob Velocity instead of Gain. Kind of confusing the way it is.
I don't have X2, but I believe what you guys are looking at
was labeled Velocity in previous versions.
It's a velocity trim, and I agree that gain is not entirely accurate for what it does.
The behavior you are seeing seems kind of odd, though.
And the "clipping" is not clipping at all. It is simply a MIDI note indicator, and has nothing to to with volume or velocity.
MIDI itself cannot clip. However, if the velocity/volume values are too high, the synth audio output can indeed clip.