Did you ever find a solution? I'm facing exactly the same issue. Can anyone from apple respond to this? If there is no solution I guess the only way would be to have a hidden unlock feature with external licenses, but technically this isn't allowed by the appstore policies. So what's the "official" way of doing these things?

What do you mean? The api is still available and the behavior shouldn't change between MacOS versions. Especially since it produces invalid packets.

For anyone interested: The behavior on MacOS and iOS is slightly different, yet both cases are annoying. I managed to resolve the MacOS issue by using the MIDI2.0 api, and sending sysex using the dedicated sendSysex method. Important: Block sending any other requests until the sysex callback has been received. On iOS however, midi seems generally broken, regardless of which API is used: When sysex is sent (using sendsysex) all midi messages after that for the next 500ms are simply dropped and not delivered. Sending sysex directly with a MIDI 2.0 UMP packet doesn't do anything at all. As far as I can tell there is no workaround to quickly send sysex and note/cc events, which makes my entire platform broken in the apple ecosystem.

Did you find a solution? I'm facing some similar issues

Submitted ticket with more details: https://feedbackassistant.apple.com/feedback/12194198

Facing the same issues, I've 1:1 copy and pasted the details, but I'm getting the same "Organization ID or name invalid" error. In addition I can't see the organization name anymore of any previously added orgs. The API just returns "null" as name. Any solutions?

I received the same email. All age related questions were already fully answered. Either we're overlooking something or the email just was sent to all devs?