Finally found what was eating all the RAM :D

Re-enabled the tone key selector in Soundboard
Soundboard now uses OutputStream, like Replay
Constexpr'd a bunch of consts which were going to BSS section
Exiting an app now goes back to main menu
Cleaned up Message array

firmware/application/ui_navigation.hpp

@@ -70,8 +70,14 @@ public:
 	T* push(Args&&... args) {
 		return reinterpret_cast<T*>(push_view(std::unique_ptr<View>(new T(*this, std::forward<Args>(args)...))));
 	}
+	template<class T, class... Args>
+	T* replace(Args&&... args) {
+		pop();
+		return reinterpret_cast<T*>(push_view(std::unique_ptr<View>(new T(*this, std::forward<Args>(args)...))));
+	}
 	
 	void push(View* v);
+	void replace(View* v);
 
 	void pop();
 	void pop_modal();