Huawei CSSR decrease after active EDGE

Hello ,

I faced strange problem when i activated the EDGE the CSSR decreaed and when i checked the counters effected i found Emergency calls increased ….. but during the trace (A, Abis ,Um) there were no failure

Its very strange doesn any one meet this problem before

Note that only few sites which have this problems , also in each sites the three cells affected at the same time which i am suspecting transmission problem .