Experienced intermittent one way audio. Also, inability to pick calls back up once they were put on hold. Inability to transfer calls, would get msg "key is not active here", and calls would intermittently disconnect when we tried to answer. These problems were present, but fairly limited until we had an unexpected power outage. When the system came back up, all hell broke loose. It got so bad, we had to go back to the 3.3. Any help would be greatly appreciated.