H D M I

OK using a Dell inspiron 15 model 3542 that I got 10 days ago and this comes up.

Using win 8.1; when I hook my H D M I cable up to my flat screen T V the video is great but the audio is coming from the bloody lap top speakers not the T V speakers ! ?

I want the audio from the T v set of course amazing; annoying it s not set up like that when purchased  !

So how do I get sound from the flat screen with using the H D M I  cable; can t figure that out nothing is going right with the sound so what now ?  ?  ?

Thanks I do did some help .  .  .