E63 - one way voice on incoming calls...

[padams]

Hi,

I realise this is a development forum, not support, but people who use this forum understand the details in SIP, VoIP & NAT traversal - and I hope will know the answer.


I have an E63 with up to date firmware, linked to an Asterisk 1.6 PBX via an Ad-hoc WiFi network. There is NAT involved. The E63 registers without problems & stays registered.

If you place a call OUT from the E63, there are no issues.

If you place a call IN to the E63, it rings & you can answer the call. You cannot hear anything from the person calling IN, but they can hear everything from the E63.

I'm assuming this is a NAT traversal RTP issue, but I'm struggling to find how to fix it.


I've tried UDP & TCP. I've tried reducing TCP & UDP refresh rates down to 4.

I've tried with & without specifying the Asterisk server as a Proxy server.

No difference.


I 'think' I need to use a STUN server to fix this - but I've tried searching for Stun server and Asterisk 1.6 and it seems that there is no STUN implementation in Asterisk 1.6


This works on a Windows mobile phone using a SIP client so I'm hoping this is just a config issue for the Nokia client. I'd welcome any suggestions.


regards

Paul Adams

[padams]

Update - the issue is not the Nokia client.

The Asterisk PBX also connects to a Panasonic PBX using H323. Further testing shows it's only calls from the Panasonic to SIP devices connected to Asterisk that are affected.

Calls between SIP devices connected to Asterisk work fine, including the E63. The problem is between Asterisk & the Panasonic, (H323)


Further update - if you answer the call on the E63 and cannot hear anything, put the call on hold & then take it off hold again. The call then works fine.

I fixed the issue by answering the incoming call from the Panasonic PBX in the Asterisk dialplan first, then dialling out to the E63. It now works without issue each time.


Regards

Paul Adams