Hi ALL,
 

I'm facing some strange issue with my VoIP Setup. I've configure 5 servers :

1. 192.168.20.1 = SER / MediaProxy
2. 192.168.20.2 = MySQL
3. 192.168.20.3 = Presence
4. 192.168.20.4 = Asterisk for PSTN with A2Billing
5. 192.168.20.5 = Voicemail

First Problem:
I've created few users on my SER and they are able to call each other (Users are behind NAT) but if User A calls User B and User A disconnect call from his side the User B phone keeps on ringing until User B disconnects the call.

Second Problem(Only some time):
when user dial  PSTN number they hear ringing on there side but other side has picked up the phone and they started to talk also but calling side is still hearing the ring.

Third:
Some time users complain that there calls are getting disconnect (PSTN Calls) after 20-30 second, I feel its more related to my PSTN Provider but how can I prove so I can tell my provider about this problem.

Please provide your feedback. thanks in advance.

I've attached my ser.cfg file b'coz if I'll paste message will be big so.
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