I think they might be mosquito eggs.
They seem to be arranged in a pattern similar to what you see. Assume they come in a variety of sizes and colors depending on species.
https://youtu.be/bXjmPLYjdTY
Jeff
My Jandy VS also makes a little soft squeal when first starting to rotate. This video sounds much louder and "harsher" than mine. I would definitely ask Jandy to watch that video.