To clarify, I'm not running the IVR. I have a TDM T1 that comes in to an AudioCodes Mediant 1000 (SIP Gateway) which goes to a FreeSWITCH machine. I receive calls coming in off the T1 which goes through my Mediant 1000 which goes to my FreeSWITCH machine which makes an outbound call back through the Mediant 1000 to an IVR (bridging the inbound and outbound calls). I have (supposedly) configured the AudioCodes Mediant 1000 to pass the DTMF in-band, because I want to minimize the amount of modifications I make to the audio stream going through my system. I also want to be able to log when DTMF events occur for analysis purposes. If I do not have start_dtmf, then FreeSWITCH does not show me any DTMF in the logs, but when I have it on, it will.

Here's a DTMF event in my FreeSWITCH logs:
(I changed the debug message to a notice and added the callId and the nano time of the event)
2009-05-26 16:02:05 [NOTICE] switch_ivr_async.c:996 inband_dtmf_callback() 348323 61182225861200042042@10.1.10.10 DTMF DETECTED: 5
2009-05-26 16:02:05 [DEBUG] switch_rtp.c:1322 do_2833() Send start packet for [5] ts=1217893935 dur=160/160/2000 seq=55199
2009-05-26 16:02:05 [DEBUG] switch_rtp.c:1258 do_2833() Send middle packet for [5] ts=1217893935 dur=320/320/2000 seq=55200
2009-05-26 16:02:05 [DEBUG] switch_rtp.c:1258 do_2833() Send middle packet for [5] ts=1217893935 dur=480/480/2000 seq=55201
2009-05-26 16:02:05 [DEBUG] switch_rtp.c:1258 do_2833() Send middle packet for [5] ts=1217893935 dur=640/640/2000 seq=55202
2009-05-26 16:02:05 [DEBUG] switch_rtp.c:1258 do_2833() Send middle packet for [5] ts=1217893935 dur=800/800/2000 seq=55203
2009-05-26 16:02:05 [DEBUG] switch_rtp.c:1258 do_2833() Send middle packet for [5] ts=1217893935 dur=960/960/2000 seq=55204
2009-05-26 16:02:05 [DEBUG] switch_rtp.c:1258 do_2833() Send middle packet for [5] ts=1217893935 dur=1120/1120/2000 seq=55205
2009-05-26 16:02:05 [DEBUG] switch_rtp.c:1258 do_2833() Send middle packet for [5] ts=1217893935 dur=1280/1280/2000 seq=55206
2009-05-26 16:02:05 [DEBUG] switch_rtp.c:1258 do_2833() Send middle packet for [5] ts=1217893935 dur=1440/1440/2000 seq=55207
2009-05-26 16:02:05 [DEBUG] switch_rtp.c:1258 do_2833() Send middle packet for [5] ts=1217893935 dur=1600/1600/2000 seq=55208
2009-05-26 16:02:05 [DEBUG] switch_rtp.c:1258 do_2833() Send middle packet for [5] ts=1217893935 dur=1760/1760/2000 seq=55209
2009-05-26 16:02:05 [DEBUG] switch_rtp.c:1258 do_2833() Send middle packet for [5] ts=1217893935 dur=1920/1920/2000 seq=55210
2009-05-26 16:02:05 [DEBUG] switch_rtp.c:1258 do_2833() Send end packet for [5] ts=1217893935 dur=2080/2080/2000 seq=55211
2009-05-26 16:02:05 [DEBUG] switch_rtp.c:1258 do_2833() Send end packet for [5] ts=1217893935 dur=2080/2080/2000 seq=55212
2009-05-26 16:02:05 [DEBUG] switch_rtp.c:1258 do_2833() Send end packet for [5] ts=1217893935 dur=2080/2080/2000 seq=55213

Does the fact that switch_rtp is sending packets mean that FreeSWITCH is sending out-of-band DTMF as well as recognizing the in-band?

Thanks for your quick replies, hopefully this will make my issue clearer.

-Drew