Keeps forgetting launcher choice

Brand new 4a5g, fully updated. I installed Nova Launcher on this thing and it keeps forgetting my choice for launcher. I'd say a few times an hour if I hit the home button it brings up the prompt to ask which launcher I want to use. I always select "Always" for Nova Launcher. If it's any relevance I have switched to the three button navigation, don't like the gestures.

Anybody experience this and know how to fix it?