Interesting: you pitch forward just as your break parallel.
I think the issue may be related to your bum-tuck and how your break parallel: your core bracing is being compromised slightly as your bum tucks under, and the forward lean happens as you try and "get lower" into the squat.
It happens in all three of the reps: you're just about to hit parallel and you lean forward, tuck your bum in and then grind back out... probably because your glutes are off and your trying to pull the bar back into the correct position. Looking at the bar path. your seem to draw a loop with it into and around the hole.
What causes this? I'm no expert, but I don't think you're keeping your back tight. Secondly, I think you're not consciously controlling your knees sufficiently, meaning your glutes turn off at the bottom (hurrr hurrr). This results (I think...) in your pelvis pushes forward through your knees (watch your knees during the bottom of the squat). As a result, you are losing a huge amount of elastic energy from your muscles making it harder to drive out the hole and preventing you from progressing.
To fix this, you really have to make sure you get your core position correct: keep your chest up (depending on your squat, this could also mean "elbows down) - even if it feels like you will fall backwards (the bar is behind you, anyway, so just dump it if you get twitchy). Secondly, make sure you always keep your glutes on: my coach recently tried a cue for my snatches which is "pull your knees up and out" during the a snatch: I found this initially restricted my depth as my glutes adjusted, and stayed 'on', which was unfamiliar as I'd gotten so used to just diving under the bar (incorrectly).
Just my two pennies.