After upgrading Call Manager from 3.0.11 to 3.1.3a, I have a problem whereby one-way voice is experienced by a pstn call after it is taken off hold/transfer. The ip phone gets 2-way voice and is tx'ing and rx'ing packets. The h323 gateway is running 12.2.7a. The "show call voice" output indicates that there is no rx packets at the gateway after the call has been taken off hold. Hold/transfer of internal calls works fine. I tried downgrading the ip phone load id to different versions, including the original load id used with CM 3.0.11 but still had the problem.