I didn’t know it was broken but apparently, the Model D just got some updates in the shape of firmware 1.1 and there were some issues to address.
Model D 1.1
The issues included sorting out the Poly Chaining to make it easier to use, improving the retriggering reliability when playing legato notes, and the introduction of a new Synth Tool app for configuration over USB with added support for MacOS.
The Poly Chain is all about connecting a bunch of Model Ds together to create a polyphonic synthesizer. Previously it was done with SysEx messages but now it’s all about the Synth Tool app. To set it up you need one Model D connected via USB to your computer. The rest are chained MIDI THRU to MIDI IN. You can chain up to 16 of the things – that would be amazing. There are three voice modes: Single notes, Chords and Unison. They all make use of the connected synths in different ways in order to maintain polyphony and minimise note stealing.
The update is available from the website.