Help external sd card problem(galaxy pocket duos gts 5302)

[qromwel]

since i had my gakaxy pocket duos gts5302,i've not been able to use my external sd card for more than a week in my phone because i always get cirrupted media files after storing them on the external sd.i've tried different external sd cards but all the same.my pics,musics and applications always get corrupted after days of successful storage when i try moving files from internal sd to external.what mught be the problem,pls help me.