The 1300PL uses a helical rack and pinion drive for higher rigidity and accuracy, and therefore will often be louder than other drive systems or similar machines.
Y-Axis gantry belts are loose.
Solution 1 - Inspect belt tension
Remove the motor belt cover over the servo motor pulley.
Remove the belt covers from both sides of the gantry.
Loosen the two mounting bolts holding the belt tensioner. Adjust the tensioner until the belt is tight
enough to only deflect 0.125" (3 mm) when pressed with one finger.
Tighten the tensioner mounting hardware and repeat for the other side of the gantry.
Loosen the mounting hardware for the servo motor.
Slide the servo back in its mounting slots until the belt is taught. It should deflect about 1/16" (1.5 mm) when pressed with one finger.
Tighten all mounting hardware and re-install belt covers.