Some of the first steps toward working with Arduino is understanding how to write code for it. The good news is that it's made with beginners in mind.

You can then wire in your new aux cord or Bluetooth input up to the other pins on the toggle switch. The toggle switch then selects between standard operation, or the external feed.

Our go-to is the LCD display and controller reference we covered here back in March. It’s a great resource, but turns up bupkis on this particular display.