I have some additional questions for you. If you haven't tried all of these, please try them and reply with your results.
Are the USB sticks USB 2.0 or 3.0?
Have you tried USB 2.0 and 3.0 ports?
Have you tried an NTFS formatted drive?
Have you tried moving files in safe mode?
If you copy a 1k file are the symptoms the same as if you copy a 10GB file?