i bought a sandisk extreme 512gb micro sd card (true capacity 481.3GB) designed for 4k video, however i only get an average write speed of 2.4MB/s and about 61MB/s reads on an app i bought called “True SD card capacity/Speed Test Pro” .
it passes all the tests up 35% capacity using this app, so it doesn’t look like it’s losing data.
i thought it was a fake micro sd card when i noticed the disney+ app downloaded video to the micro sd card and then displayed files only containing a few megabytes or kilobytes that were unplayable, and sometimes crashing the disney+ app, but it doesn’t seem to be fake according to the testing app, just slow.
i am currently running another test using the mentioned app up to 52% capacity but it’s going to take days.
what kind of write speeds am i supposed to be getting?
is it possible that it is a counterfeit sandisk micro sd card and that it’s designed to fake the passing of the tests?