I will have to run a test to get the exact order that causes it to occur.
I do NOT use auto play. I am mixing manually.
If memory serves, it is when (for example) if the track in Deck A is ending, and ANYTHING is loaded into the sampler decks (playing or not) the "MASTER" jumps to the sampler deck that is loaded, even if you have a track ready to go (or even playing) in Deck "B".
What ends up happening is when you go to "SYNC" the tracks, Deck "B" syncs to the Sampler BPM instead of the BPM of the track in Deck "A". The only way to avoid it is to leave the samplers empty and not use them.
In my opinion Decks "A" and "B" should be the "primary" decks when Cross is set up in sampler mode; there should be an option (in the preferences perhaps) to disallow them from becoming MASTER decks, because you can SYNC them manually anyway. I don't know why anyone would want to set up a sampler deck as the source for the MASTER BPM anyway. It makes sense when using them as traditional decks, but not as samplers.
I'd rather have my samples match the BPM in Decks "A" and "B" then have Decks "A" and "B"try to take the master BPM from the sampler decks, which is what it does now.
Just give us an option to disable Decks "C" and "D" from becoming "MASTER" decks, and the problem is fixed.
Hope that makes sense.