Dust is the biggest enemy of optical sensors. Regular cleaning is crucial:

1. Turn off and unplug the machine.
2. Use a soft-bristled brush or compressed air to remove dust from the hopper and stacker.
3. Gently wipe the optical and UV sensors with a dry, lint-free cloth.
4. Never use water or harsh chemicals on the sensors or rubber rollers.

We recommend a professional deep clean every 3-6 months depending on usage.