I am constantly being annoyed by my girlfriend/friends constantly messing around with the radio, changing the channel, cranking it super loud, messing with the bass, etc when im driving. Ive told them not to but they still do so basically im just wondering if there's any password protected audio systems that would stop them from doing that. im looking to upgrade my audio anyway so the password would be a huge bonus. Also something that could completely block out certain frequencies entirely would be great.

If anyone knows of such a thing/things then it would be hugely appreciated!!