Default wallpaper always goes to black?

this just happened randomly... when i set the wallpaper to one of the standard nexus wallpapers it always flashes the wallpaper on my home screen and then goes to all black? if i set a live wallpaper it stays fine. and if i set a wallpaper from a backgrounds app those stick around (but they are super small, assuming cuz they are not HD?) anyone know whats going on and how to fix? i have tried a reboot and all and doesn't help... i should also mention that i was not messing with wallapapers when it started. i opened plants vs zombies and it crashed and thats when it started. but i can get into plants vs zombies now with no issue?