Polyend Medusa firmware

New Features: Added a 6-voice 3-operator digital FM synth engine. Reworked pitch bend and glide. Improved “Channel per Voice” mode. Added MIDI Program Change. LFO Synchronization with MIDI Clock. Added a per-preset option to “Skip muted voices” during voice selection in P1 and P2 mode. Fixes: Fixed digital clicking at note start. Improved analog AMP envelope release handling (no clicking on the release of the last held note). Long note releases are no longer cut short when no notes are held. When a second held note is released in Mono mode, the first one returns with the last one’s volume instead of full volume. When a note is pressed when no voices are available in Next voice priority, the least recently used voice is taken over (note that in the First voice priority Medusa will not play another note if all voices are used, this is deliberate). Auto-calibration now uses a smart timer that increases intervals as the device warms up. Increased responsiveness when a lot of USB MIDI data is incoming. Incoming “all notes off” and “all sound off” MIDI CC messages are now respected; Sustain pedal (CC64) is now supported in all play modes (MIDI hold mode). Changing Pads Root Note, Layout, Scale, or MIDI Middle C while notes are held no longer causes hanging notes. MIDI aftertouch no longer causes hanging notes in Mono mode. Amp envelope in all polyphonic modes is now updating on the screen. Allowed skipping muted voices in P1 and P2 modes. Allowed unselecting the only playing note in Hold mode in M play mode. Fixed sequence playback in Grid mode always using First note priority in P1 and P2. Fixed held note continuation in M mode being interrupted after Sustain pedal was released. Made held legato note continuation in M mode work when both MIDI input and pads are used. Made the Channel 9 mono synth in DFM mode ignore the Sustain pedal (it’s only used by the polyphonic FM voices, just like Hold mode). [...]