They should not be that loud, I suspect one of three problems.
A) The front cover is loose, check the gap all around, make sure it is securely on the motor, if it is loose or crooked it will be very noisy.
B) The glass it is mounted on is less than 1/2" thick, on thin glass the magnet is very strong, compresses the rubber feet and transmits a lot of vibration, a thin rubber piece should be added to reduce this. This can also happen if the pump is in the corner and touching the side wall directly.
C) The titanium shaft is bent, remove the drive unit from the shaft and roll the shaft on a table, if it has a bow or wobble this is the problem, let me know and we will send a new one.
If the noise is not that dramatic, this can be normal on new pumps, a rule of thumb is 50% of the noise is gone after 2 weeks of wear and 75% is gone after 2 months and that is when they reach there optimum. This occurs because the parts must seat and wear in.