Some update:

I detached the EVENet controller and had the 8000 run for a while on its own and voila, out of the blue sky it changes patches w/o the controller plugged in, so its definitely nothing wrong with the EveNet remote. Based on this I can see only two possible causes: Battery life or the 5.6 update. Therefore I just downgraded to 5.5 in order to do another round of testing and so far I did not encounter the issue anymore. I'll keep you posted but looks like a bug…

Regards

John