in my opinion its because of the smaller size of the card. 32gb vs 64gb. with the smaller card it finds the files faster. ive got 128gb cards and some games are really slow. just my opinion.....So...i tested both cards, both sandisk
64gb class10 64k cluster
32gb class4 64k cluster
Both formated with guiformat
SOMEHOW class4 runs twilight princess REALLY smooth.... Loads between maps are faster than 64gb class 10
Dont know why