Diagnosis
You're overloading the blade assembly or using an improper technique for hard, frozen items. The motor is laboring against a solid mass.
How to Fix It
- Stop the blender immediately. A sustained grinding noise can damage the drive socket.
- For crushing ice, never fill the container more than halfway with cubes.
- Always use the 'Crush' or 'Food Processor' Auto-iQ program for ice. Do not use 'Blend' or 'Smoothie'.
- Start with a small amount of liquid (a few tablespoons of water) in the container first, then add ice. The liquid helps carry the cubes into the blades.
If That Didn't Work
The issue might be physical. Remove the container and inspect the blade assembly. Ensure the blade unit is screwed on tightly to the container base (turn clockwise to tighten). Also check the drive socket on the motor base for any broken plastic teeth.
Heads Up
This blender is powerful, but it's not a commercial unit. For best results and longest life, pulse hard items in 2-3 second bursts rather than holding the button down continuously, allowing the contents to settle between pulses.