I recently noticed after updating my phantom 4 with the latest firmware that the gimbal was somewhat twitching/shifting left to right during flight. I observed this after reviewing playback where the camera appeared to be tilted at times.  I also noticed that in the caliberation of the phantom its been asking me to tilt the phantom on its side instead of facing it down on the second part of the caliberation. Is this normal or do I have to run some basic tests to ensure proper caliberation? I have never had this problem until my recent update of having to position the phantom on its side to caliberate. Are there any suggestions out there for me on how to address this gimbal and caliberation issue?

Have a look at This other link regarding tilt.

There are five calibrations in total on the P4.

Optical Sensors (calibrated using DJI Assist 2 on PC or MAC)
IMU calibration (calibrate on level surface, a cool temperature allows for faster 'IMU Warm up' when aircraft powered up )
Gimbal calibration (done just after IMU calibration)
Compass calibration (this is what you describe above, it does not seem to matter whether 'nose down' or 'on its side')
Finally RC 'stick & gimbal wheel' calibration (performed with aircraft powered off.)

EDIT :- You could always try a 'factory reset' of aircraft if none of the above work  (DJI Assistant 2, Blue Button on screen). Probably best to recalibrate and check all settings after this.

Thanks I'll give it a try tonight and report the findings tomorrow if the issue continues to occur. SO, it does not look like a hardware issue in your perspective?

Horizon tilt was a prominent issue for many, just search 'horizon' (Magnifying glass at top of page) and you'll see a few. It was suggested many times that this could be 'fixed' through firmware. And for a number that seems to have been the case.

And if it has just appeared after an update then that surely points towards the update, or perhaps one of its files not installed properly or corrupted (could try firmware refresh)

Hello 3rdIvisions, please try to reflash the firmware via DJI Assistant 2. Then re-calibrate the IMU and gimbal. If the issue still exists, please open Aardvark's link in #2 and follow steps in #5 in that thread. Post them here. Thank you.

Today I was able to calibrate the imu, before initiating the process I noticed that one of the levels on the gyroscope was significantly higher (.17) in comparison to the other three (which were at .3). I then restarted the phantom 4 and calibrated the compass. On my flight test my phantom 4 seemed to be working right back to normal which I'm happy to report. The phantom 4 maintained a stable height without shifting too much, granted it was kinda windy out today so I was really impressed. My last observation however, was noticing the weak signal indicator which kept appearing in and out of the screen at about 200ft., the phantom 4 did not appear to loose control but I found it strange because I was in an open space. Other than that I'm happy to connect with this forum and the great information that comes out of it.

3rdIvisions Posted at 2016-6-21 22:10
Today I was able to calibrate the imu, before initiating the process I noticed that one of the level ...

"My last observation however, was noticing the weak signal indicator which kept appearing in and out of the screen at about 200ft"

The aircraft wasn't directly above you when this happened was it ? If so then that would explain.

Aardvark Posted at 2016-6-21 17:20
"My last observation however, was noticing the weak signal indicator which kept appearing in and o ...

I flew a little over the weekend and it appears that the issues with signal loss was just probably something related to the area I was flying around during the time. Other than that, phantom 4 has been flying great since I followed the suggestions for my little problem. Thanks everyone and dji.

3rdIvisions Posted at 2016-6-28 03:04
I flew a little over the weekend and it appears that the issues with signal loss was just probably ...

Correct, most always video issues are resolved by moving to a different area free of interference.