The scenario is that you are using one of our ProTalk Door Entry SIP phones with a Gradwell account and forwarding the call to a mobile phone. You might want to do this to talk to people at your door when really, you aren’t in or for when you aren’t near a desk phone in your place of work.
If you still want to operate the relays in the door phone (either to activate a door opener, turn on a light etc…) then you type in a certain sequence on the phone you are using. This sequence is transmitted back to the door phone using what is known as DTMF tones. In order for this to work with Gradwell accounts we’ve found that you need to use their Outbound Proxy.
Firstly, make sure you are on a recent firmware (v1.48 at the time of writing), you can get this from ProVu if you need to upgrade. Then set the device up as follows in the SIP Parameters page:
- SIP Proxy Server Address – nat.gradwell.net
- SIP Proxy Server Port – 5082
- SIP Registrar Server Address – sip.gradwell.net
- SIP Registrar Server Port – 5060
Then your username/password as Gradwell will have given you.
This may also be the case for other providers as well as Gradwell, so if you are getting one-way-audio problems or DTMF problems in general, ask them about Outbound Proxy.