this is probably because the note-off will be transposed and the vsti won't know that the note-off corresponded to the original note-on. there are two possible fixes - one is to keep track of any playing notes and not transpose their noteoff (this would be a lot of work). the other would be to send an all-notes-off on transpose note changes. not sure if that's easy either.

the last option would be to not use the JS effect to transpose, use shift 9/shift 0 on the midi item directly to transpose the item like that.

dub3000, thanks. I know those workarounds, but they are too distracting from making music. It would be really nice if there was midi transpose plugin that would just simply do transpose, but not make musician stop making music and find those note-offs and so on.

Tracking note-ons isn't really feasible for a simple MIDI FX to do -- the transposer would need to reset and scan back to find open note-ons on seeking the play cursor, etc. A native transpose function could do this, but that's not what the JS are. So, although the issue is understandable, it's not a Reaper bug.

schwa, that's great, where can I find plugs or something with those "native transpose function"?

pan.Krutilkin, "a native transpose function could do this" means "a transpose function implemented in reaper could do this"...

Jeffos, that's why I ask for an plugin or something with that feature/function or an example how can I do really normal transpose without note stuck. If there is no possibility to do that yet, than I'll post feature request.

We can improve JS/MIDI/transpose I think.

Thank you, schwa :)

I usually hit f3 to get rid of the stuck note(s). An automated note-off of the affected notes would be good enough for me. :)

This is the type of stuff that really should 'just work' out of the box. Hanging notes are really embarrassing. +1 for improving JS/MIDI/transpose and for a native implementation.