[sciurius]

As it had happened already once, a year ago, also on this specific stage, but with different tablet and different bluetooth pedal:

You may add: And a different version of MobileSheets and Andoid OS.

To me that is a strong indication of either a specific and peculiar way you treat the devices during this kind of performance, or some source of bluetooth disturbing radiation.

The first alternative you can test at home, by re-running the performance as closely as possible.

For the second alternative, try to get hold on a FireFly (or other USB pedal) and connect it via USB to see if the same problems turn up.