Sound comes through speakers and headphones

[Android Central Question]

So, my phone is almost brand new, I got it in october. When I plug headphones in it's all good sound's perfect. Only thing is when I take them off and leave the music going I can still hear sound but not from the headphones. It comes from the speakers. So both work simultaneously.
If anyone could help I'd appreciated it a while lot. Thank you

 

[belodion]

Make sure they're plugged in fully.