MainStage 3 Randomly Transposing Patches

Hey All,

So here is the situation: I use Mainstage 3 on Mavericks with 2 controllers via USB: A yamaha S90xs and A Novation Impulse 49. I use the mac's 1/8 inch out to send audio to a direct box. I have 4 Mac's of all different models and my issue happens with each one of them at random times.

My Issue: every now and then (quite often) after letting it sit for a few minutes (no screensaver or sleep mode enabled), I will play a patch, and it will be randomly transposed 1.5 semitones. It will happen on any patch, even new ones i create, and it will go back to normal by simply moving to another patch and back. There is no way to accurately reproduce as it is completely random. Only that it happens often and unexpectedly. I can play a song, touch nothing on my controllers and/or computer, and come back 10 minutes later and it will be off 1.5 semitones. It will happen with either controller (but even wierder if I'm using them at the same time, it never happens to both, only one or the other).

Has anyone ever had this issue? if so how did you solve it?

Thanks