Hello everyone, apologies for my first post being a request for help, but I'm somewhat baffled by what's up with my Phantom 2, and I'm eager to get it up-and-running again. I miss flying Yesterday, I popped the top off my Phantom 2 and I performed a few upgrades: Fitted a mini iOSD, which is taped to the front (inside) of the drone Moved the anti-interference board, for the gimbal, from outside to the inside, removing and refitting two screws (attaching it to the main board) - I can't really describe where, but I can find out if it's significant. Moved the CAN-bus from one of the legs to the inside (I attached it to the main board with a little bit of folded-over tape Fitted an ImmersionRC 600mW transmitter to the underside of the Phantom 2 using velcro Today, I took the drone out to try the video and noticed a few things: The drone appears to drift, definitely more than it used to (I can't remember if it always drifts in the same direction, relative to the direction the drone is facing) There's a squeaky noise coming from the rear-left motor (I think it's that one...) The rear-left arm appears to vibrate (upon which the motor which I suspect is squeaking is mounted) I cut a few cable-ties off to re-route cables and didn't put some new ones on, but I don't think (I'm not certain) that it'd cause the symptoms I'm seeing. I grabbed a video of the vibrating/squeaking sound... ...and one of the drifting... I've tried a few advanced IMU recalibrations, plus a swap of the propellers for a new set, but it didn't seem to make much difference. I think the squeaking stopped on one flight, but the drifting was still present. It's definitely doing it again now (before the second recalibration), though. I have a few questions: Is there a chance I've misaligned the IMU, so I need to do the 'paper trick' whilst calibrating? Could the squeaking be caused by compensation from the misalignment? Could the motor be iffy and causing the drift? (I guess I'd need to check if it always drifts in a particular direction) Could adding the iOSD mini and ImmersionRC require me to adjust the gains? (I didn't have to whilst adding the Gimbal, which was the bulk of the weight) Thanks, and apologies for the longer-than-I-expected first post!