Paul Hayes presented the following explanation :

>
> What firmware version have you got on it? You should only hear one tone if
> only one of the DTMF mode boxes is ticked, what you are describing sounds
> like what happens if you've got "Audio" ticked as well as one of the other
> modes.

Hello again, Paul. Any news on the updated firmware that will allow the
R key to function on a SIP call?