Odd fuzziness in my slideshow

Mnemosyne

So, when I had first uploaded this, I didn't have any problems. Now when I upload it, somewhere within the first few slides (approx. 24 in), they progressively get fuzzy and blocky, and then eventually it stops. Anyone know what's causing it?

I encoded at the highest quality possible in iMovie (not resolution, the actual part that gives you the slider for quality). The only thing I can think of is that around that same point in my project file I set the timeline to lock the audio to the video, so I could fix some of the text in the beginning, but I can't imagine something like that affecting the quality of the video.

Also, I double-checked the actual video file. The fuzziness doesn't occur in the original file. Only when I look at the uploaded version.

This hasn't occurred in any of my other slideshows, and only occurs at that point in the slideshow that I can see.

Since the embedding process isn't working for some reason, it's the last slideshow in this gallery.

Also, I tried reuploading it, didn't help. I've tried re-encoding it, that didn't help either. I just can't fogure out why it's doing this

http://mnemosyne.smugmug.com/Portfolio/Portfolio/9439065_NvYiG/1/640282507_BvWg5