Form 2-3 weeks i have some problems with incoming ISDN calls, it
interrupts after 1-2 minutes of call. I have tried to debug this with
pri set debug on span 1, i have noticied much of this messages:
Just to help with troubleshooting you could try to reproduce the same problem with a different set of SIP endpoints. Setup a soft phone as the destination and see if the problem occurs there. That way you can eliminate the handset as a potential problem.