The family has known failure modes; here is what to watch for.
1. Install Light Blinking
The install light blinks when the pint or outer bowl is not seated. Reseat the pint flat and lock the lid down before starting again.
2. Machine Not Powering On
Check the outlet and the back connection first. If it still will not power on, do not take it apart; the one-year warranty covers service, so contact Ninja.
3. Blade Not Spinning
The usual cause is a frozen pint with a domed top. Scrape the surface flat before processing; a lumpy top can jam the blade.
4. Grinding Noise
A grinding rattle that starts suddenly or worsens deserves attention, apart from the normal roar. Stop the run and inspect the blade; a unit that grinds every run is a warranty claim.
5. Plastic Shavings in Ice Cream
This is the serious one. The blade has cut into the pint itself, leaving stringy plastic in the batch; in the worst case we tracked, it happened on every container within fewer than ten batches. Stop using a damaged pint and return the machine under warranty.