Amazon has not been able to help! The 128GB SD is fire HD 10 tablet approved and has been tested as OK with h2testw. Can download books etc. , but movies load 350mb to 1.5GB and then get a DISK_10_error and download stops. Followed all fire trouble shooting steps and also reformatted SD. Can download fine to the internal tablet storage. Cannot find what DISK_10_ error is as not on Amazon or Google? All Amazon says is to do the trouble shooting steps of force stopping video and clearing data. Any ideas would be appreciated . Device is Fire HD 10