Hello all, Well, I have the weirdest problem. 3CX support and my trunk provider also can't seem to figure it out, so I'm posting it here in the hopes that someone has a suggestion. Situation is as follows: -1 Extension -1 Trunk with one phone number directly connected to Extension 10 -Extension 10 is set to forward to 'my mobile' after 20 seconds If the phone number of 3CX is called, it goes as follows: -Extension 10 rings for 20 seconds -Mobile phone rings for 7 seconds -Extension 10 rings for 20 seconds again -Mobile phone rings for 7 seconds again. This repeats itself. You can answer the Mobile phone if you want and have a normal conversation. Now, the strange thing is, when I set the 'forward after... ' time to 10 seconds, it goes as follows; -Extension 10 rings for 10 seconds -Mobile phone rings for 17 seconds -Extension 10 rings for 10 seconds -Mobile phone rings for 17 seconds. This repeats. In both examples, you see the time adds up to 27 seconds. And I can reproduce this and vary this. Set 'forward after...' to 5 seconds and the mobile rings for 22 seconds. Set it to 25 seconds and the mobile rings for just 2 seconds.... I have Wireshark captures sent to 3CX and those captures show the CANCEL coming from the trunk provider. I can believe that, I see it to. HOWEVER, why does the trunk provider cancel the call? And how can they possibly know after how many seconds they "have to" cancel the call to make a grand total of 27 seconds? This just seems impossible. The trunk provider is saying the problem lies with 3CX, 3CX says it lies with the trunk provider.... Normal calls through the trunk provider obviously go well and never get canceled. Does anyone have any idea how on earth the trunk provider 'knows' exactly when to cancel the call? In some manner 3CX must be specifiying this, since only 3CX knows what the 'forward after' time is set to? (one more remark, I have also tried setting up a Ring Group that forwards to an external number. The result is almost the same, difference being that after the 27 seconds have elapsed, the call is completely terminated. Eg. the 'return' to ringing all extensions in the Ring Group does not occur, but the external forward is canceled in exactly the same manner). Attached are two screenshots showing the point a bit more clearly, I hope!