Chosen Solution
My Samsung J3 5 media volume only plays through headphones and when I make a call it only works on loudspeaker. Also when I turn phone on it seems to be stuck in headphone mode even when they’re not in.
@westernstacey sounds like a stuck headphone jack. Insert your headphones and remove them a few times in rapid succession. It is possible that this will unstuck the jack. If it does not you have to consider replacing the headphone jack. This guide Samsung Galaxy J1 Logic Board, Main Camera, Front Camera, Earpiece, Loudspeaker Replacement will help with that. Of course you also want to try a restart on your phone as well.
