Thank-you for the preset, @Luk_Vermeir
I set it up to be sufficiently like yours to be able to test
- Notes → mA
- Clock → mB
- mapCC → mD
(mapping the Arp Properties and Sustain On)
I can’t reproduce your glitches, I’m afraid: mine behaves exactly as expected; sustaining all notes while Sustain is on then dropping all “expired” notes when this is switched off.
No hung notes.
I did wonder cos I remember this similar bug report last year was fixed by firmware 1.13.2 which I assume you must be running.