Never had a vaginal queef situation, but I can tell you I was going fast and heavy with a lady doing a very wet BJ once and the same thing happened. A pocket of air trapped in her mouth got squeezed out and rattled her cheek making it sound like a loud, wet, farting noise. We were both quiet for a good 10 seconds kinda surprised, when and she exclaims, "My mouth just farted!" We almost died laughing afterward; good times!
It wouldn't bother me at all, and I've been curious if you can actually feel anything when it happens.