Can you check the recorded MIDI data for the correct Control Change message?

Sostenuto is CC66. That will tell you at least if it is getting recorded from your MIDI device in the first place.

(Not to be confused, separately, the Sustain Pedal is CC64)

Tip: Use of the Event Filter may be useful:

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Last edited by VideoTrack; 01/11/22 01:44 PM. Reason: Added screen capture

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