Changing DTMF Signaling

[MrSIP]

Hi,

I have just purchased a Nortel (LG) 1535 phone, but DTMF button presses are not being detected when receiving a call from our SIP door entry system.

The system is expecting the DTMF signalling to be 'SIP Info'.

I can't find any way to change it on the phone. Does anyone know if I can change the DTMF signalling in 3CX for Windows, or on this model phone?

 

[tsukraw]

Normally there is a setting on the phone to change this, but im not familiar with this phone. the issue being though i don't know if you would want to change it to SIP INFO unless that all this Nortel phone is doing is talking with the door phone?

Reason being is if you use it for every day calling you might run into issues with IVR/outside menus requiring button input since most of them want RFC2833.

If you'd like shoot me a PM and Id be willing to remote on with you and take a look at your phones menus and see if there is a way.

Have you also looked at the door phone and verified there is no way it will support RFC2833?

Thanks