New controller: EBS brake sound, weak torque and midride throttle problem

Hi all,

After using single drive e-scooter for a while I wanted to go the dual drive way.

My problem is the new controller. I attached new controller to old single drive setup to try it. Throttle is weak, electronic brake is weak and makes noise, at the middle of acceleration the scooter suddenly brakes with a strange sound without reason. Hill climbing is almost zero compared to my old controller.

I have converted Oxelo 7XL kick scooter with custom rear fork + 8 inch rear hub motor setup with Chinese brand Brainpower XLH75 36V controller. Old one was with LCD, and it works well with or without LCD screen. 10S 5000Mah Zippy battery, 2x5s in series.

New controller is also Brainpower, but without LCD. Brainpower KSLU26

I uploaded 2 videos to youtube for the diagnostic purposes for you.

[youtube]bqNtOixjTGs[/youtube]
[youtube]j2hZUgAFzk0[/youtube]

Edit: I discovered that the sound is not continuous. I hear it when hub motor hit some specific angles.
[youtube]2x0UKUkFwGc[/youtube]


I suspect a faulty mosfet or other component problem with this new controller. What do you think?

What I tried:
- I tried new controller with my old motor and old controller with new motor, new controller is the problem
- There is a green cable for making controller learn the motor, I used it, no change
- Tried without plugging in the brake, no change
- I used old one without LCD to compare, old one works normal
- There is a cruise switch cable attached to controller, I disconnected it, same problem (what is the use of that, Idk)

Edit: I contacted the seller and they will replace it. Still, I am curious about the reason of this problem.