Issue Description
A customer said that they were unable to make calls or dial internal extensions. They are able to receive calls though.
Handling Process
The customer captured the 7910 data package when the issued occurred - 488 error code means the media negotiation failed.
But other 7910 Asterisk phones call successfully. We advised customer to disable SRTP on the 7910 phone and only use RTP. The test was OK.
Root Cause
Asterisk PBX does not support the SRTP protocol.
Solution
Disable the SRTP function on the 7910 phone.
