Your Alphabet, Math Quilt is Adorable !!
OMG you may get to keep it for yourself, :) then can mend when snuggled up in it this winter, eventually you will have the whole thing done by hand. Easy Peasy ;)
(just teasing) Good luck with it.
Only thought to why or idea why it's doing that, have ran across dropped stitches at higher speed, and they stopped at lower speeds may be time for a service.