SIP trunk problem on UC520

[renatorados]

Hello. I have a problem with SIP trunk on UC520. Actually I can make a call but I cannot hear anything and no one can`t hear me.

I`m using a simple SIP provider with user name, password on 5060 port. Preferred voice codec is G711ulaw  Can any one know what can cause this problem? Thanks in advance.

[saif musa]

Check if there is any firewall process befor or after your UC520, as long as you can make a call and there is no voice streaming then it's something related to RTP streaming.

Regards