Irig stomp I/O not working with IPad Pro

Hello, pls help. I have two IPads Pro 2 gen and irig stomp I/O. After few minutes IPads not find Irig and there was no sound... My ios is 13, also I rebooted my iPads and reinstalled app (GarageBand and Amplitube) but doesn’t help. Also I checked my iPads in service center- was no problem. The same problem with two iPads. I checked irig stomp I/O with iPhone 6s and pc - was no problem, all working good. So the problem only with IPads Pro. Ikmultimedia can’t help me, they say - ask apple. So pls help me!!!!