Hmmm very strange problem!

I've just received a new MMM ESC from CC.
But the new ESC is acting very strange.
10-20 percent of fwd and reverse throttle range the motor has a lot of lag (cogging). Passing the 10-20 percent the motor is working fine.

I had tried:
Other tx and rx > no luck.
Recalibrate the ESC > no luck.
Other lipos > no luck.
Othe motor > no luck.

Anyone any ideas?
Or I will send it back:-)

Thanks in advance.