Some notes are not playing during playback

Version: 2.1.0, Revision 871c8ce

Problem: Certain whole notes are not playing during playback, while others do. In other parts of the song, whole notes, whether tied or not, play just fine. However, in two spots (that I have found), they do not play. In both cases, the whole notes are tied for at least three measures; the notes are in the first and second voicings. In the first case, there are quarter notes in the bass clef that play back without problem, and no additional voicings in the treble clef; in the second case, all notes are whole notes, with two voicings in both the treble and bass clefs. The piece is formatted in grand staff with the name of "Piano" in the mixer, but the sound set to "Voice Oohs." The notes are not in any abnormal range.

Attempted fixes: deleting the notes and re-inputting them, changing the mixer sound to a different instrument, then back to "voice oohs," reinstalling the program, reverting to factory settings, changing soundfonts (the same issue persists whether in the stock soundfont or with Arachno). After all of these actions, the sound will still not play back.