Jerky playback on certain clips, only in Program window

There are a few clips in my Premiere timeline that are really jerky when I play the video back (like 1FPS), though everything else is fine.

Also, the frames from these clips sorta 'stick', even as the timeline indicator moves to the next part of the video. I have to pause playback and then press play again for it to play properly

If I view them in the Source window they look fine.

I have proxies for them and also tried clearing my cache multiple times, tried muting FX too but with no luck.

Is there a way to sorta 'pre-load' those particular clips in my timeline rather than having to export an mp4?

If I press 'enter' to render it, then Premiere attemps to render every clip in the file, which is overkill.