Silent calls

[maahsan]

If this problem happened on a new commisioned BSC, re-homed BSC, BSC on which Ater were added recently than most probable it is caused by CIC mismatch or cross patching on A-interface.

You can ask your NSS team to do a dial test in which they will force call from a certain IMSI to be routed to each E1 on A-interface. That's how they can narrow down which A-link is cross patched or has CIC mismatch. You won't have access to core network to do it on your own.

[Md.Moniruzzaman]

We faced this same problem while working in Grameenphone network.
Vendor was Huawei. The problem was in the TRFO node.
The problem occur while speech coding trying to change from AMR to Non-AMR

[almoqbali36]

we have same issue in our network but the vendor is ******** and switch is huawei, the problem not always some times we did trace for the calls but nothing appear.
and I have one intresting senario which i did during the drive test:-

"during my drive test I make a call and it has silent call and then I hold the call and make another call. B number answer the call it was fine not silent call then I tried to join the two calls but they droped both"

[khalidsaif82@gmail.com]

it is related to CIC


please perform CIC test between msc and trc

please check if there is any blocked Devices .

[zloy_qwer]

Also you can check statistic with CIC usage.