Steve, you're right - with <param name="uuid" value="true" /> most log lines have a uuid. But look at the following example - we tested entering DTMF digits from two calls simultaneously. As you can see, for each call there is only one line which has a uuid and several others which have not. There is no way to separate these lines in case you need more information on this issue - especially if you image having 30 or 100 simultaneous calls. 2013-09-19 14:28:46.453687 [DEBUG] ftmod_wanpipe.c:1678 [s3c17][3:18] read wanpipe event 3 2013-09-19 14:28:46.473372 [DEBUG] ftmod_wanpipe.c:1678 [s3c16][3:17] read wanpipe event 3 2013-09-19 14:28:46.613375 [DEBUG] ftmod_wanpipe.c:1678 [s3c17][3:18] read wanpipe event 3 2013-09-19 14:28:46.613375 [DEBUG] ftmod_wanpipe.c:1547 [s3c17][3:18] Queuing wanpipe DTMF: 9 2013-09-19 14:28:46.613375 [DEBUG] ftdm_io.c:3778 [s3c17][3:18] Queuing DTMF 9 (debug = 0) 2013-09-19 14:28:46.633372 [DEBUG] ftmod_wanpipe.c:1678 [s3c16][3:17] read wanpipe event 3 2013-09-19 14:28:46.633372 [DEBUG] ftmod_wanpipe.c:1547 [s3c16][3:17] Queuing wanpipe DTMF: 3 2013-09-19 14:28:46.633372 [DEBUG] ftdm_io.c:3778 [s3c16][3:17] Queuing DTMF 3 (debug = 0) 2013-09-19 14:28:46.633372 [DEBUG] mod_freetdm.c:815 Queuing DTMF [9] in channel FreeTDM/3:17/453025556 device 3:17 2013-09-19 14:28:46.633372 [DEBUG] mod_freetdm.c:815 Queuing DTMF [3] in channel FreeTDM/3:16/453025556 device 3:16 90a6c771-f499-489b-b956-96807707e611 2013-09-19 14:28:46.633372 [DEBUG] switch_channel.c:471 RECV DTMF 9:2000 899aa236-8a86-4433-9f9c-734f985023b3 2013-09-19 14:28:46.633372 [DEBUG] switch_channel.c:471 RECV DTMF 3:2000