Since upgrading from 13 to 15.1, MIDI communication is unreliable (mostly nonexistent). Using Apple lightning camera USB adapter.
and 3 keyboards including XWP1. After extensive talk with Apple support, it seems a Firmware update is required by each keyboard manufacturer to make the KeyStep communicate MIDI with iPad iOS 15.1. (Apps tested include GarageBand, MidiWrench, ForScore.)
Anyone have a similar issue?