Ha, thanks and sorry for the lack of info there, and I see how this could be relate to many, many variables.
I'm using mainly synthesizer software instruments, like Alchemy (non-samples), Sculpture, FM8, Massive, Chromaphone. Occasionally using EXS24. I'm definitely noticing the problem with Chromaphone
However, I think I really need to do some more controlled testing of this issue on different instruments, and different settings, and I'll get back to you, hopefully with new insights!
Thanks!