LAGGING WITH MEMORY CARD

has anyone else experienced the frequent lag and restarting when using a memory card in the phone? when i try to flick scroll through my pictures, the phone freezes for like a few minutes then restarts and then it works fine for about an hour then if i scroll again, it freezes again and restarts again. also, when i try to open up the music player and choose a song from the memory card, the phone freezes and restarts. i tried to get my phone repaired at the ATT warranty center in the local store and the lady said that just because its a touch screen, its going to freeze every now and then. i dont think she understood that i dont want a phone that freezes every hour or so. i got a replacement phone and the new one does the exact same thing. she also mentioned that it could be because i had a full length movie on my memory card and it just took time trying to read it. (i have the hangover on there BTW). does anyone have any solutions because im really tired of this phone and its problems. im thinking about selling it via craigslist and getting the pantech link from ebay so any help would be appreciated

Maybe a defective phone? Try using it without the memory card first.

If it still lags, then backup and do a master reset.

If it still lags, then go flash it.

If it still lags then your phone is defective.

i tried reformatting and it still lags a lot. when i use the phone without the memory card everything works fine but i dont have room for my music or anything on the phone itself. maybe ill try flashing it. what should i do if after i flash it, it still lags?

the card is... *checks card*... its sandisk 8gb

ok ill reformat on the computer right now and see what happens.