Hello Arlo. For the last couple of gigs, I have been having a problem with Device Linking. Two gigs ago, the link was lost on three occasions. During the last gig, I lost the connection at least half a dozen times. On one such occasion, the master iPad even closed down SetList Maker though I don't think those two issues are necessarily related. I haven't made changes to any settings in either iPad over the past couple of months, apart from the usual updates.
Please submit a help ticket here:
https://helpdesk.arlomedia.com/arlomedia
Then tap Help > Send Troubleshooting Info in the app and enter the assigned ticket ID.