i have many sd card no issues
i would back up the info on the card to your pc, reformat it on pc to fat 32 & disk check it for errors
then format the card on the tab, all devices the sd card should be formatted by its device only.
that does not mean that a device non-formatted wont work but it is recommended.
i had an evo shift with same issue, i did a quick re-formatted & check disk on the pc, then put it in the phone and it worked, but then i also reformatted on the phone, it works fine.
and yes plenty of fake cards out there, buy only sealed retail packs for a little more money to avoid that issue
u can also dl some free programs online to check it, speed test it & reformat it for phone use