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Created by Ryan Harris, last modified on 2018.02.08


integer Sets the reverse twist setting in the spandsp DTMF detector. Reverse twist is set to 4 dB by default. This value can be safely increased up to 6 or 7 without a significant increase in talk-off to allow DTMFs that exceed this threshold to be detected. Set this variable prior to executing spandsp_start_dtmf.


<action application="set" data="spandsp_dtmf_rx_reverse_twist=6"/>
<action application="spandsp_start_dtmf" />