I have my 2820 IPPBX working perfectly with my SIP account, and have analogue and IP Softphone registered happily, but I cannot persuade my Avaya 9620L handset to register.

Various firmware's produce a variety of results on the handset, the best acheived so far is actually logging into the handset successfully, but the handset never gets beyond 'Acquiring Services'. I know that the login has been successful as if I deliberately use incorrect login details, then they are rejected.

Has anyone successfully connected any other IP handsets to the IPPBX?

Thanks

Bit further forward now. Have Avaya handset registered and able to make and receive calls except.......no sound in either direction. Doesn't matter whether call is internal or external....just silence but at least a step in the right direction.

The Avaya handsets use G729A as their default codec and am wondering if this is an issue?

All done..was bit complicated but I now have analogue, Avaya IP, and softphone handsets all connected and working happily without the Draytek locking up after every call. Crystal clear audio as well.