Heads-up guys about audio issues with v6.3 PR1 and ACD or UCD hunt groups using extension lists in a multi-node environment.
If there are off-node phones present in a hunt group extension list, phones on the local controller will have no audio when calls are answered.
Placing the incoming call on hold, then retrieving it, will restore audio. Phones ringing individually (not in an extension list) will work properly.
Mitel has multiple reports and is investigating.