Live CC data visibility and playback in Up-stem Voice 1 for IVP instruments

Sorry for the long title, but I think I’ve located a rather specific bug.

Suppose I’m intending to write with two voices, Up-stem Voice 1 and Down-stem Voice 1, which I’ll call V1 and V2 for now, on an instrument with independent voice playback (IVP) enabled. I’ve found that, under some circumstances, some live CC data for V1 is not displayed or played back, even though it is “recorded”.

I’ll give an example of how to recreate this bug. Begin with a hard restart of Dorico [] (sometimes this bug goes away if you repeat this experiment with Dorico open, even on a new project), create a new project, add any instrument, and give yourself three bars to play with.

  1. Record some notes with live CC data in bar 1 on V1.
  2. Record some notes with live CC data in bar 2 on V2.
  3. Record some notes with live CC data in bar 3 on V1.
  4. Enable IVP.
  5. Notice that the live CC data in bar 1 does not display or play back, but bar 2 and bar 3 are fine. If you disable IVP you will see that it is there (that is, it has been recorded), but after enabling IVP again, it is hidden once more.

If you delete, then re-record the notes with live CC data in bar 1 on V1, everything is now fine. Even if you delete everything and start again, everything is fine. It feels as though anything recorded on V1 before another voice will have its CC data ignored.

I’ve found that even if I make sure that IVP voices are instantiated before I start recording, the same bug occurs.

Also, if you start a new flow within the same project after having gone through the steps above, this bug seems to occur again in the new flow.

If I’ve diagnosed the problem correctly (I’m only 75% sure of this), then a workaround is to make sure not to record on Up-stem Voice 1 first when working with live CC data on an IVP instrument; record something on another voice first, then everything will work fine.