Stuttering at low power

[KiZ]

Hi folks, I just got a brand new 3650-3300 v2 through the door today.

Now I'm fairly green when it comes to larger scale brushless stuff, I've been mostly doing 18th scale electric for the last few years, so go easy on me, but I noticed that when I plugged it in to my MM and gave her a little spin (I lightly held the rotor to load it), it cogged/stuttered until about 25% power. Even with no load at all, it wouldn't start rotating until about 25%. Battery is a Maxamps 5000 3S.

Is this normal? Do I just need to raise the start power on the MM? My castle 5700 starts straight away from extremely low power.

And is it ok/recommended to cover up the holes? They are pretty darn large and I would hate to get a stone in there