Spotify control with earphones samsung galaxy s4

[joses]

hello to everybody,

i use spotify with my new samsung galaxy s4

the control in my earphones (original that comes with s4) doesn't respond correctly to commands,
for example only the volume up and down works,

if in my devices storage give none song only the play button of earphones works correctly with spotify,
else start the song in music player samsung (instead of command in spotify).

i want to understand if it's a problem with spotify version in my galaxy s4, or maybe i have defective earphones

thank you