1. followed logging procedure to enable verbosity & debugs
2. set extension mapping in end point manager to use  tls & srtp template
3. set device 4984 to use encryption
4. rebooted polycom ip670 phone from freepbx gui
5. phone rebooted second time as done with major config changes
6. dialed system voicemail *97 and logged in
7. placed call on hold and resumed twice
8. pressed * to keep vm connected
9. dialed another call to VM, failing login
10. conferenced both calls together
11. disconnected calls

Here's where the problem starts:

12. dialed VM again, reached fast busy signal on phone.

13. same thing on this attempt.

14. dialed outside number 800-444-4444 but reached fast busy signal.