Cisco SPA525G Administration Guide - Page 267

SPA and Wireless IP Phone Field Reference Ext Tab B Parameter Silence Supp Enable DTMF Tx Method Description To enable silence suppression so that silent audio frames are not transmitted, select yes. Otherwise, select no. Defaults to no. Select the method to transmit DTMF signals to the far end: InBand, AVT, INFO, Auto, InBand+INFO, or AVT+INFO. InBand sends DTMF using the audio path. AVT sends DTMF as AVT events. INFO uses the SIP INFO method. Auto uses InBand or AVT based on the outcome of codec negotiation. Defaults to Auto. A codec resource is considered allocated if it has been included in the SDP codec list of an active call, even though it eventually might not be chosen for the connection. If the G.729a codec is enabled and included in the codec list, that resource is tied up until the end of the call whether or not the call actually uses G.729a. If the G729a resource is already allocated (and since only one G.729a resource is allowed per phone), no other low-bit-rate codec can be allocated for subsequent calls. The only choices are G711a and G711u. Since two G.723.1/G.726 resources are available per SPA9X2, you should disable the use of G.729a to guarantee support for two simultaneous G.723/G.726 codecs. Dial Plan The default dial plan script for each line is as follows: (*xx|[3469]11|0|00|[29]xxxxxx|1xxx[2-9]xxxxxx|xxxxxxxxxxxx.). Cisco SPA and Wireless IP Phone Administration Guide 265