That's a bit of a tough one. We've never heard from someone with that specific problem before. It could be a problem with the iPad or with the H9. iPad Airs in particular have had flaky Bluetooth connectivity problems, but the problems we've heard of in the past applied to people trying to connect multiple H9s to an iPad Air. There are a couple of different problems that can occur if an H9s Bluetooth chip isn't soldered correctly, but again, those problems typically have different symptoms than what you're describing.
You're powering the H9 with the Eventide power supply? B/c under powering the H9 will usually affect the Bluetooth functionality before anything else…
If I were you, I'd probably do the following. I'd reset the H9s system settings by turning it off and turning it on again with the right footswitch and the HotKnob switch pressed (the switch in the upper left hand corner of the H9), and I'd reset the iPads network settings by going into the iPad Settings app, then to General Settings, and then to Reset Settings. And I'd check if the problem went away.
If you had another iOS device or another Bluetooth device to try with, that really could clear up what the source of the problem is. Since you don't, it really becomes a matter of guessing what the more likely source of the problem is. If my suggestions above didn't help, then I suppose you should consider either returning the H9 to the store you purchased it from, or sending it in to us to take a look. To do the latter, you'd want to send an email to firstname.lastname@example.org with the serial number of your H9 and a link to this forum thread.