@jingleperson if your keyboard still keeps playing through the speakers instead of the headphones, it is most likely the headphone jack that is at fault. Once you insert the jack on of the contacts will close and should turn the speakers off. Of course you want to try another set of headphone and see if that makes a difference. SOmetimes you can free up the contacts inside the jack by inserting and then removing the headphone connector a couple of times. Do that a couple of times and see if that will free it up.