First, I would strongly encourage you to purchase either a power rack or get a sturdier set of squat stands. I would have issues too if I had to rack and re-rack the weight with those squat stands. Get a power rack and I guarantee your issues will subside. You are messing around under the bar because those racks are awful.
Depth is eh. The first two were okay. The last couple were high because you are not getting tight before you squat. And you are losing tightness with each rep. You could stand to open your stance out a little wider and make sure to finish completely. Stand all the way up and lock out your legs. Take a big breath, pause, squat, Stay TIGHT and drive up with your hips and lock out at the top. Pause and take another big breath and repeat. You are not tight when you come out of the rack because you cannot get tight in that flimsy rack. It amazed me that you were able to rack the bar. Get a power rack. Please.