The Customer trying to call from outside analog line to the AT0 trunk and hear busy tone but when trying to call from mobile call recived by the IVR
1. Make default user from the AT0 trunk to make the call recived
2.Make auto answer for the default IP Phone of the EXT we added in the default AT0 trunk and decrease the time of the auto answer to 0 > call faild to recive and hear busy tone
The problem is when u1960 offhook more quickly, peer system will be failed to recognise the offhook and send busy tone
run this command
config modify timerinterval pid os_pid_vu timergroup 0 timerindex 5 interval 3000
now we add the offhook time to 3 seconds to solve this problem.