It happens to me sometimes. Usually it's just loud, noise.. Not sure what to call it, lots of random noises at once. A few times I heard a loud voice, and once it sounded like maybe our door got kicked in. Very annoying. I think it happens more when I'm very stressed or have a messed up sleep schedule.
I also don't think it's very rare, quite a few people experience this at least once, but no most people don't have this frequently.