Slight shake from the camera

[xfreedommasterx]

For a few weeks now, I've been noticing from my recorded videos a slight shake in the videos being recorded. Its not something I can see just looking at it but its noticeable in the recorded videos. I'm not really sure what to make of it. I have done the IMU calibrations a couple of times and it doesn't seem to help. I'm wondering if anyone else has experienced this and if there might be a fix for it. My earlier videos are really smooth which is why I'm asking cause I can't really do anything with the videos if they are shaky even if its only a little bit.
I should also note that I have never crashed it or hand any hard landings. I just seems to have started gradually without me noticing it.