I am currently using Cubase 5, windows windows 7 64.

I previously used Cubase AI4 on the same system.

Both often and quite unpredictably would change my settings anytime i stopped or started playback. The program would change the settings on various VST's.

On some projects it never does it, and on others it's all the time. What can I do to fix this?
I found out a bit more info. I use tux guitar which is a midi writer of sorts.

Cubase is assigning things from the VST's presets that relate to the sounds in tux guitar. Not that they sound similar, but if i use piano (first preset slot in tux guitar) then I'll get whatever the first preset slot is in whatever VST I was using in cubase.

It only does this after i press play.

Any help?