[Q] Slow MicroSD performance (Fat32, 64gb)

I followed some instructions to organise FAT32 mode on a 64gb class 10 genuine sandisk card (I've checked / benchmarked) so that CWM would work on it.


Problem is, Winamp for example is taking FOREVER to load the thumbnails for my music located on the SD card :/ It's like there's a slow disk access problem.
Is this a known isue? Have I done something wrong?
Any thoughts on this?

Thanks all