I have 2 PJSIP clients that worked fine for months. They both started failing auth on August 28 around 1:30 in the morning Pacific Daylight Time.
My logs captured the event:
2019-08-28:2019-08-29,01:34:02.457 WARNING MainThread account.onRegState 0 171100 401 sip:address@hidden
2019-08-28:2019-08-29,01:25:57.602 WARNING MainThread onRegState 0 171100 Unauthorized 401
After this event, every subsequent registration fails with "server rejected with stale=false". This has been going on for over 2 days now.
PJSIP Status 171100 = PJSIP_EFAILEDCREDENTIAL.
The docs for PJSIP_EFAILEDCREDENTIAL say
"Credential failed to authenticate. For this failure, right credential
for the realm has been found and used to authenticate against the
challenge, but the server has rejected the authorization request with
401/407 response (either with no stale parameter or with "stale=false"
parameter). In most cases, this indicates that the username/password
combination is incorrect. "
Something is broken with the linphone sip server, it is rejecting valid username/password combinations.