Fuck muzei.
Get CLARO instead. Much smoother in my experience with both apps. Claro has complete customization. At what time you want changes to happen, if you want it to be random, a sequence or even have some filter on the wallpaper. Can be a bit buggy i heard but worked fine for me.
https://play.google.com/store/apps/details?id=com.bhanu.autochangewallpaper(there's also a free version)
