This happened again at rehearsal last night - an iPhone that worked at the last gig would crash as soon as I selected the online DL32R.
Again, to fix, I just changed one fader, saved the show, reloaded the show... Then that device would open.
It was getting disconnected at first too, but as I changed settings on another iPad, it began to work again.
What worries me is - what if I didn't have 3 devices, and only had one, showed up to run sound and my iPad would keep crashing out??? There would be no show unless I forced the mixer to reload the firmware again...
Guess I will show up 2.5 hours before every show, instead of of just 2.