i have some cisco phones which are registered on my freepbx. these phones are working perfectly. its just that randomly i see the below message in the asterisk cli. During that time the phone wont be able to make outgoing calls. but after a few minutes of seeing the error the phone registers back by itself without any intervention and resumes working. This happens at random times i.e during the day, sometimes during the night. what could be the issue?
NOTICE chan_sip.c: Registration from '<sip:[email protected]>' failed for 'x.x.x.x:51817' - Username/auth name mismatch