i have problem with my digium TDM400P, i need to restart my machine to get outside dialing everytime it fails to make a call. So, some calls are succesfully done but in the third call (by example) it does not make nothing more and the need to reboot my computer is necessary, the message i receive from asterisk are two: one is about a zap channel which cannot be reached or used to make the call, and the next is the following is this, but the call does not occur.

 -- Executing Dial("IAX2/monkey@monkey/2", "Zap/5/012464625203|60") in new stack
 -- Called 5/012464625203
 -- Zap/5-1 answered IAX2/monkey@monkey/2

 any idea about this problem?