Hi,
I think this is a bug, I did not notice it before update 4.0.1.
When I record a chord like C-E-G using the Paraphonic button, then play a melody keeping some keys pressed simultaneously, and release gradually, the chord stops being played as it should but a note keeps being played indefinitely and it is not a chord. Playing some staccato note stops the stuck note.
Best wishes for 2022!