Card scan wrong?

Played a session last night and had something weird happen with the card scanner at the table. It was one of those auto-shuffler games with the hole card reader built in. A few times, the dealer was getting either a 10 or face card showing, did the regular peek, and it just seemed off. Like the dealer stared at the light on the scanner for way longer than usual and then still manually checked under the card with their finger before continuing the hand.

Has anyone noticed these scanners glitching out sometimes or giving the wrong read? I tried to pay attention if the deck was stacked weird or dirty, maybe messing with the sensor, but nothing obvious popped out. Kind of got me thinking about all the reliance on the tech instead of old-fashioned checking. Wondering if I should actually trust these machines or if we’re just pretending everything’s running smooth for speed’s sake.