Hi,

during the last weeks, my new custom build is having some strange issues. Build on rotorbuilds
The "funny" thing is that I need it for work in 2 days and so I have only tomorrow to make it work properly   please help me!    

I've noticed that in the last flights, usually after a sudden change in throttle value, the quad tends to flyaway even if I go to zero throttle. It takes some seconds before being able to recover it. It's behavior is strange, it's like it gives some punches of throttle for me, when in fact I am on zero throttle position

i've checked for the blackbox logs and I've noticed a very noise gyro, but I'm not very expert in tuning and filtering.
For sure the Cineboy camera mount is awful, so a lot of vibrations are due to the moving piece of carbon fiber that holds the camera while it is not steady. 

You can clearly see what I mean in the video linked below (sorry wasn't able to post here the video as attachment, it continued to throw errors)

On the bottom left corner you can see my throttle value (on OSD) and there are 3 points (at least) where this effect is clearly visible (at the start after the first descent, one in the middle, and the final crash where i lose control at zero throttle 10m away from the impact area).
I've noticed that the motor 4, when this problem occurs, is completely OFF, while the others continue to spin hard.

I tried to flash different BF versions (last 3) but the problem still persists.
Could you please help me to find out why my 3inch started this weird behavior? Have you already experienced this?

thank you so much for the help and for your precious time and expertise. 

i would softmount the moving-cam-mount, some hotglue could be used probably.

check the capacitor leads, are they still connected? add a second one could probably help