ok – and what is the error : number unreachable or network error ?
in terms of qos stats, can you see what’s wrong? is it sdcch assignment failures ? or paging failures?
i would say that either
(1) the called party is detached from the network (due to location update problems), or
(2) the paging phase is not completing properly
(3) the immediate assignment phase after the paging is not completing properly.
(3) would have a symmetrical impact on MO calls
about (1), it seems unlikely, but just to be sure, let’s do the following test : once a MS on this BTS has called you, can you call it back without any problem ?
if yes – then MS was indeed detached
if no – then MS attach/detach is not a problem.
about(2) – check your paging timer T3113 (as far as i remember), and there are perhaps others.
about (3) – here again, i would focus on the timers involved (there are more than 1)
Can you do a A interface trace? See what is happening after the paging is sent?