Hi All, Several of my PRIs in India have recently been getting this error from time to time. Every time it happens, I can temporarily fix it by restarting FS: 2014-02-03 13:11:25.713142 [NOTICE] mod_freetdm.c:2728 Hangup FreeTDM/3:4/0942847XXXX [CS_INIT] [REQUESTED_CHAN_UNAVAIL] 2014-02-03 13:11:25.713142 [DEBUG] switch_ivr_originate.c:3639 Originate Resulted in Error Cause: 44 [REQUESTED_CHAN_UNAVAIL] Our system sends 30 calls at a time to the PRI gateway, and this error comes up on any one of the channels. The channel is not in use at the time, based on 'show channels'. FreeTDM does not bypass the channel and try another, so if it's channel 14 that's unavailable it doesn't move on to 15, and only 1-14 get used (until I restart FS). Sangoma support has examined a trace and found the d-channel on affected lines fluctuating. Also I notice that around the time this problem crops up the line suddenly flicks signals: 2014-02-03 17:25:00.877663 [DEBUG] ftmod_sangoma_isdn_cntrl.c:45 [s2c1][2:1] Signalling link status changed to UP 2014-02-03 17:25:00.877663 [DEBUG] ftmod_sangoma_isdn_cntrl.c:45 [s2c2][2:2] Signalling link status changed to UP 2014-02-03 17:25:00.877663 [DEBUG] ftmod_sangoma_isdn_cntrl.c:45 [s2c3][2:3] Signalling link status changed to UP 2014-02-03 17:25:00.877663 [DEBUG] ftmod_sangoma_isdn_cntrl.c:45 [s2c4][2:4] Signalling link status changed to UP 2014-02-03 17:25:00.877663 [DEBUG] ftmod_sangoma_isdn_cntrl.c:45 [s2c5][2:5] Signalling link status changed to UP ... I'm also wondering whether I should give a time gap between originate commands? Perhaps inserting a half second or so between calls will prevent the channels from getting jammed up. I'm not sure where the issue lies. With the telco (fluctuating d-channel), with FreeTDM, perhaps with my Sangoma hardware or driver (currently running 7.0.8 and libsng_isdn 7.28.0)? Thanks, Neil