Playback not working with 8vb

Hey there guys, I noticed on my score that 8vb was not working for the playback at some point.

I still run 3.3.4 (I'm the guy whose computer cannot properly install the software, remember? lol). I managed to solve the situation by erasing the section and pasting it somewhere else in the score (pasting it where it was before did not fix the issue). Also, as I realised about the bug, I used the undo buttons to undo whatever triggered it, but the bug wouldn't disappear (even though I was undoing actions even up to before the 8vb line was even added). Let me know what kind of info you need.