We have configured a couple of iphones for a customer of us using Cisco Mobile 8.0. Two of Iphones are working fine, but the other two stops ringing after two rings. The configuration on the CUCM (6.1.5) and the software on iphone are all the same. Anyone got any suggestion how to sort out this issue?
Check the iOS version of the iPhones
Are they all the same? e.g 4.0.1 vs 4.0.2 vs 4.1
Check what other features are configured for that user that may be affecting the calls e.g. SNR, Mobility Reach, CFNA, CF timers, VM etc