2005 prius squealing

Hint: use a hair dryer to soften the plastic a bit so you don't break anything and pay attention to the air flow arrows on the filter. I believe the video got it wrong - Air flow is down, that's why the top of the filter is dirty. It'll work either way, but it'll do a better job if it's facing the correct direction. There's an up arrow on the filter door because it only latches in that direction. If you point it in the wrong direction, it won't latch.

Hope this helps... and you don't find a chewed-up filter in there.