Just recently a couple users have reported an issue that when a voicemail comes in, all the wav file contains is "An error has occured" message. This is an intermittent error as the rest of the messages come through fine. This seams pretty rare, though one user had this happen twice yesterday. I've gone through the logs, though nothing appears for this issue or user at this time.
Currently I am using Unity 5.0(1) and it is linked with Exchange 2003.