I'm with you, I clean and sanitize after every hatch. Then I put a freshly washed shelf liner in the bottom each time. The water I add has a bit of Oxine in it. Can't be too safe from the bacteria.
I had this with my male border collie, Riley. I was painting the room that holds my incubators, so the table was pulled away from the wall. He was circling the room (duh, what else would he be doing............he's a border collie, LOL), anyway he ran along the wall behind the table and the wire from the genesis to the power bar caught on his stifle as he ran by. The incubator hit the floor, all the eggs tumbled from the turner and a few cracked. It wasn't mischief on his part and I love him more than the chickens anyway.
It was my fault for not locking him up while I was working in there. Anyway, the eggs that didn't crack mostly hatched without problem.
I was more upset the time the same exact thing happened with one of my female border collies, Ceilidh. But the wire her leg caught on was attached to my laptop. It hit the tile floor and had to be replaced.
Once again, totally my own fault
Dogs, ya gotta love em!