It sounds like this is still a problem, and it sounds similar to a problem that I ran into on my server last month but hadn't gotten around to processing a report.
I'm running 7.0.7 on the server but a player found that if there are two bells placed next to each other, one rings while the other doesn't. They can then break the second non-ringing bell and glitch the ringing one to ring indefinitely.
They made a video here:
https://www.youtube.com/watch?v=4hxZ2HD ... e=youtu.beIt's long but most of it is him just waiting until nightfall / over several days to see if it ends up spawning something, which it doesn't. If these are related and unsolved, hopefully it helps pinpoint the problem.