When the wife enjoys the system? Let her have it and listen to whatever she wants. They are not into it like we are but if they can appreciate if just as much as we do?
Let them be and let them enjoy.
Yeah, you may lose the system for an hour or two but it allows them to truly appreciate music, like they have never heard it before....or probably ever will again. Let her embrace it, enjoy it and get lost into the music like we do.
In the end, it will bring you closer and she will understand (at least my wife does) why we are all so heavily involved in our hobby.
Tom