I also experienced this too recently. This problem is also persisted in other roms with AOSP theme changer installed (e.g. latest versions of Corvus, Superior OS).
Only roms with "Styles & Wallpapers" theming app installed are safer from this problem*. Derpfest, Revenge OS, PE, Havoc, and more.
*your accent may still reset if your rom is corrupted from force reboot when using certain kernels