Asteriks DTMF

Anyone know how to adjust the DTMF settings. I am using a SIP phone to test a dial plan and am having issues with the authenticate and read commands. I will press a number once but it will read as if it was hit two times. Any help would be much appreciated.

voip-info.org/wiki/view/Asterisk+DTMF

there is a section about duplicate dtmf.

regards,
derek

Thanks Derek. Seems the issue was on the SIP phone.