Hello list, I've been having a problem for some time now that I can't figure out how to solve it. On a PTP BRI ISDN line, if I have both channels in use and I place a third call from the outside, I'm not getting a busy tone like I should. Instead I get a congestion tone, as if the line was not working/didn't exist. Currently I'm using mISDN 1_1_9.1 and Asterisk 1.4.35 with an OpenVox B400P and I've tried all possible combinations of PTP/PTMP and with or without the termination jumper on the card. I've also tried to make it work since mISDN 1_1_8 and Asterisk 1.4.18. This is the message I get in Asterisk when the third call tries to come in: P[ 4] channel with stid:10020400 in use! P[ 4] channel with stid:10010400 in use! P[ 4] There is no free channel on port (4) P[ 4] --> !! lib: No free channel! P[ 4] I SEND:RELEASE_COMPLETE oad: dad: pid:0 P[ 4] --> channel:0 mode:TE cause:0 ocause:0 rad: cad: P[ 4] --> info_dad: onumplan:0 dnumplan:0 rnumplan:0 cpnnumplan:0 P[ 4] --> we have already send Release_complete asterisk/extensions.conf (relevant part): http://pastebin.com/a9nihVKt mISDN.conf: http://pastebin.com/6FPbcqc7 asterisk/misdn.conf: http://pastebin.com/9TGmGFFR Does anyone have any idea what can be causing this? Thanks in advance, Best regards, Paulo Santos