what are your equalizer settings?

1) The seller do hard format o jz restore to factory setting???
2) Where do u save ur msn??? (in phone memory o memory card?)

If ur phone did a hard format, that means all data u installed in ur phone will lost.
Try to re-install back ur MSN again and make sure it's save in memory card.

Cannot download MSN in "download" there??? weird...
Have u try to format ur memory card too?

I jz can recommend u to format all (phone & memory card) then only install back what u need.
Save all software o theme in memory card too, if not it's hard to find the way to delete it.