Some of my users are randomly unable to join the server

Hi! Some of my users have problems connecting to my server, this appears to be totaly random of which user(s) are affected and during which time of the day. We previously had a different server but created a new one since we suspected that it might had something to do with that server.. however now we have the same issue with our new server.. I think that when a user fails to connect they end  up with an error mentioning something about webrtc. Anyone hade the same issue? Anyone got a fix for it?