strange Call Setup problem

[hamody2005]

Dear ALL


In one BTS the call setup decrease to 0 in the same hour for thee days till know and the setup failure is call resource allocation failure

Huawei CDMA BTS3606


From Log analysis I have found the All call failure are with cause value (0x2700)



Cause Value:-0x2700

Defination:-
CCB_FAIL_ADD_LEG_ACK_TIMEOUT


Meaning:-
Timeout occurs to the waiting for LCB_ADD_LEG_ACK, and the sub-branch is not successfully established


Causes:-

(1) During the establishment of sub-branch, timeout occurs to the waiting for responses, and the timer is not configured properly.;
(2) Internal errors or heavy signaling traffic between subracks causes the loss of messages.



Who could help me with this problem.