Brand new P3P, my first videos show gimbal drift, jitters, etc.  I've calibrated IMU & compass, set to "follow" mode, removed the white foam block, all software up to date.
Here is the output:   


Could it have something to do with the gain & expo tuning?


The problem has occurred with both RAW & JPG video shooting.

NO that has nothing to do with Expo or Tuning. Have you tried just holding it with the motors off in your hand and seeing what the gimbal is doing when you move it around? Try doing that inside and video it. Then we can see what the gimbal is actually doing.

When you turn on your P3. with out the props, just turned on, does the gimbal vibrate???

Other than trying the obvious (a few IMU and gimbals cals), you need to contact DJI or your dealer. This puppy is not right.

One guy said he did the gimbal calibration with it up in the air (NOT IMU, the Gimbal cal) and that solved his horizon problems.

I'm getting the idea this is a hardware defect, though, so after a couple more attempts contact DJI.

I have had the same behaviour with the gimbal on my P3, although not nearly as bad as yours.  Only 1 flight video showed the 'rocking' motion yours has, but it was probably worse.  As for drifting, when it was new I am sure the gimbal did not drift.  I don't see any evidence of it in my videos.  It worked flawlessly.  Now after about 12 flights I am seeing almost constant drifting.  If I move the gimbal by hand, it returns to position normally - no drift.  If I pick up the P3 (pro), move it around and then set it down, it drifts every single time.  It's a very slow drift like about 1 degree every 3 seconds.  I have reset the gimbal settings and recalibrated the gimbal several times.  I think I will do an IMU calibration next.
Hmm maybe I will check the sensor readings first before doing that.
I put down a sheet of glass on the carpet and used a bubble level with electronic display to accurately level it before doing the IMU calibration.  I hope it solves the gimbal drift I am seeing.

Rob  

Hi, did you finally solve this problem? I have a new P3P, firmware 1.8.8 and I am having the same problem; Roll drift while yawing