Error 12 & 13 means that it is reading a different format from your USB or SD input. Please reformat your card/USB and only load MP3 music onto it. Then remove the radio from the dashboard and unplug it for 20 mins. This will do a master reset on the unit. Plug it back in and then try it again. Make sure that you are not using over a 512MB SD Card or USB Memory Drive with no more than 249 tracks on it.