Your gonna have plenty of noise at high speed unless your using a Vesc in FOC mode.
Wiggle the shat to see if there is excessive play in the bearings. If Not turn the motor by hand and see if it feels smooth or rough.
If you have excessive play or it’s rough, replace the bearings. You really should have a hand press for bearing installation. Also check your belts for rocks.
They tend to get stuck in there.
And don’t over tighten your belts. That can wear the motor bearings out prematurely.