Dual USB: https://goo.gl/kbMEFP If you have one of the new Subaru’s from 2015 to 2017 and replace the stereo you will want to retain the factory dual USB & Aux. This is how to install the dual usb interface. Demonstrating here on a 2016 Subaru Forester.
Questions or comments email me customautosports@gmail.com.