I've been exploring all options for music, including what others are using. When trying out both an iPod and an mp3 player connected via the 3.55mm plug/jack, I get nothing. No content visible on the display, no sound, no nothing. I verified that the devices were powered on, that "Aux" was selected in the menu as the source, and that the devices themselves were playing music. The 4th generation iPod Touch that I previously used on my 2014 RT could be a compatibility issue, but I have tried two different mp3 players with the same negative results. Thanks in advance for any suggestions.