When I take a picture, two images get saved on camera roll.

[ebin5]

Me too facing this problem in my 520 for months.even black update could not fix it.a quick search in internet show many face this problem and even music files show 5 to 8 copies.

 

[anon(123856)]

I had the same issue. It took a hard reset to make it go away. The good news is if you are prepared for that, it is fairly painless.