Alan Harris

That grind is often the rubber drive coupler slipping or a failing blade bearing not the motor. Unplug it and remove the jar, and spin the blade by hand; if it’s rough or wobbly, the blade assembly is bad, and if the little star-shaped coupler on the base has chewed teeth or play, that’s your culprit. Also make sure the blade base is tightly screwed to the jar and add a bit of liquid before ramping up; dry starts on high can shriek. I’d skip opening the base - couplers and blade assemblies are usually user-replaceable and often covered under warranty.

I chase grandkids too and the thing that helped most was treating focus as a moving target. Switch to continuous focus when they are running and keep a single point on a face and then fire a short burst. Works great. If shots still look off and try a slightly higher f number so you get a bit more depth of field and push the shutter speed faster to freeze wiggly hands. Avoid focus and recompose at very close distances since the plane of focus can slip off an eye. Also make sure you are not standing closer than the lens can focus. A small step back often brings the autofocus back to life.

So frustrating. That actually pattern usually points to a safety feature kicking in or a failing part. Start with the simple stuff and plug it straight into a wall outlet, not a power strip. Hit the reset on any GFCI outlet. Let it cool fully, then turn it on and see if the timer still feels about ten minutes. If it shuts off faster when you are at the highest setting, drop the heat a notch and test again. Clean the plates & the seam near the hinge when the tool is cold. Built up residue can trap heat and make the thermostat trip early. Do a gentle cord swivel test while it is on. If the light flickers or it powers down with cord movement, the wire at the hinge is failing. If none of that changes the behavior,, the internal thermal switch or sensor is likely drifting out of spec. That is not fixable at home. If it is still under warranty, reach out. If you replace it, look for wider plates to cover more hair at once, strong heat recovery, and an auto sleep that is at least half an hour. Makes long thick hair sessions much less stressful.