I have a Phantom 1.2 and just upgraded the NAZA v2 to firmware version 4.02. The upgrade procedure seemed to go well. After flashing the firmware, I loaded the default settings, calibrated the transmitter, the compass, and the IMU, and re-enabled IOC. Unfortunately, when I powered-up the Phantom, the startup melody was very faint, almost inaudible, and when I tried to arm the motors, they just kind if flutter back and forth, rather than spin. After that, I tried doing a hard reset on the Naza. Following that, I re-calibrated everything, but I'm still getting the same issues - very faint volume on the startup melody and the motors only flutter, rather than spin, after arming. Any ideas how to fix this?