There is a firmware update for K2 to overcome an issue, whereby, the MIDI on K2 does not work when connecting to an M-series Apple Mac.

The update must be performed either on an Intel-based Mac or Windows PC. However, once the K2 device has been successfully updated on an Intel platform. It will connect and run just fine on the M-series system.

Please follow the link below and download the v2.50 bundle.

https://www.allen-heath.com/hardware/xone-series/xonek2/resources/