Trixbox - Sirrix PCI4S0 - Asterisk crashes


I am currently using Trixbox 1.2.3 (Asterisk 1.2.12) with a Sirrix PCI4S0 card. Both incoming and outgoing calls are working fine. However as soon as I upgrade to version 1.2.13 of Asterisk, everytime I receive or make a call, asterisk crashes and duly restarts. I also have a Sangoma A200 card which continues to receive and make calls without a problem.

Any assistence would be greatly appreciated.