Sorry to hear you are having issues. Have you tried “forget” on the H90 since connecting to the Mac? It may be that the Mac bluetooth is interfering with the iPad connection. Please try the following:

• Turn off Bluetooth on your Mac
• Select “forget” on H90
• Go into your iPad settings to delete the H90 Bluetooth device
• Follow the instructions to pair/connect with your iPad: https://cdn.eventideaudio.com/manuals/h90/1.7.5/content/system-menu/bluetooth.html#ipad-connection

Let me know what happens.