settings are good- but still skipping frames

I think you are talking about frame numbers. 29.97 fps footage and comps use drop frame timecode by default. NO Frames are dropped, just frame numbers. You have to skip some frame numbers to keep the time display accurately.  Your current time indicator will display the time and the closest frame number to that time, but every few frames it will skip a frame number. This is normal, expected, and required to keep the time display accurate to the nearest second.

I won't go into the history of television that caused the NTSC frame rate to change from 30 to 29.97, but it had to do with needing the add color information to the signal. There just weren't enough scan lines in the frame so they had to slow down the frame rate to add a few more.

Playback is tied to the performance of your computer.  Sometimes, even when all of the settings appear to be correct, the computer still can't handle your composition. There are a bunch of places you can check.

What's your computer spec?

What's the comp (project) frame size? Bigger is more pixels, needs more cache. You can also use a Region of Interest crop to isolate a portion of your animation.

How long is the animation you're trying to cache? Creating a shorter Work Area will buffer a smaller amount of your comp, usually resulting in more contiguous frames being buffered.

What's the comp resolution you're trying to cache?  Sometimes using a "half resolution" can give you a realtime playback and allow you to see the speed (if not the quality) of your animated layers.