MuseScore 4 notes decay before I let go of Midi Keyboard

In Muse Score 4, any time I try to hold out a note or chord when holding down notes on my MIDI keyboard, the notes decay relatively quickly (about 1 second) before I've actually let go of the keys. In fact, it doesn't matter how long or short I strike the keys, the note duration is the same. For example, if I strike the keys with a staccato articulation, the note still plays for about a second before decaying.

This is frustrating when trying to experiment with melodic ideas that require longer note durations before committing them to the score. I compose jazz pieces, and this audio issue renders any swung eigth note ideas that I play into an incomprehensible off-time mess.

Changing the rhythmic note value selection for "note input" has no effect on this issue, as I don't have "Insert" selected when playing through melodic ideas with my MIDI keyboard (or else they would get committed to the score).

After I've committed my melodic ideas to the score via "Insert", note values playback correctly for their intended durations, which included whole notes and ties.

I could, of course, 1) go back to v.3.6 or 2) experiment with compositional ideas on another keyboard or in another software, but I often use VSTs such as Kontakt to inspire melodic compositional ideas and capture them to score immediately as part of my process.

I've included a lead sheet I'm working through in Mv4 as an example. You won't be able to open it properly in Mv3.

Is there a setting I need to change, or is this a known issue with the development versions of Musescore 4?