Hi all, I am using a GSM Box with 15 sims to imitate a PRI card. But most of the time, just after the destination number is picked the call disconnects, x-lite shows an error 'Failed to establish call'. In around 1/6 times the call connects properly. Similar setups with PRI cards are working flawlessly. The relevant traces are as following: Sangoma stack trace: 2014-10-15 19:19:07.506516 [DEBUG] ftmod_sangoma_isdn_trace.c:224 [SNGISDN Q931] wp1 FRAME INCOMING: Prot Disc:Q.931/I.451 (0x08) Call Ref:0FC7 (Destination side) Type:DISCONNECT (0x45) Cause:coding:ITU-T(0) location:User(0) val:Normal call clearing(16) Progress Indicator:coding:ITU-T(0) location:Private network, local user(1) descr:In-band data ready(8) [ 08 02 8f c7 45 08 02 80 90 1e 02 81 88 ] Freeswitch debug info: 2014-10-15 19:19:07.506516 [INFO] ftmod_sangoma_isdn_stack_rcv.c:232 [s1c1][1:1] Received DISCONNECT (suId:1 suInstId:783 spInstId:863) Any suggestions? -- Sudhanshu