Hi I'm tested AudioCodes Mediant 600. I maked extensions 446. This extensions is Registered. But if make a call is not posible. I see log [Jan 19 17:06:49] WARNING chan_sip.c: username mismatch, have <446>, digest has <1129> [Jan 19 17:06:49] NOTICE chan_sip.c: Failed to authenticate user <sip:firstname.lastname@example.org>;tag=1c1993760231 Why not make a call.