Google Cardboard: Android native UI pops when starting with cardboard deactivated

I am using Google Cardboard SDK for Unity (v0.5.2 with Unity5.2.4) but I am having the following issue : I don't want the cardboard support upon application start, I want users to select it manually. I unchecked the boolean control for that in the inspector in Unity, but when I run the app on Android, I still can see the native UI controls (that vertical line and the settings button at the bottom) during the first frame the game is loaded.

Is there any way to fix that? (I'm not a java...

Google Cardboard: Android native UI pops when starting with cardboard deactivated