Subsonic not working with Galaxy S5 (noob content)

i made the switch from an iphone to a galaxy s5 and im trying to get back some of my programs.
subsonic was working perfectly on the iphone, now i cant get it to play anything and it used almost 3 GB of data trying to play one song.
that never happened on the iphone.
i read the help thread on the kitkat operating system (which i think i have), but im a complete idiot when it comes to android phones.
does anyone know how to fix this issue, and give me instructions (like talking to a 4 year old)?
thanks!
subsonic was working perfectly on the iphone, now i cant get it to play anything and it used almost 3 GB of data trying to play one song.
that never happened on the iphone.
i read the help thread on the kitkat operating system (which i think i have), but im a complete idiot when it comes to android phones.
does anyone know how to fix this issue, and give me instructions (like talking to a 4 year old)?
thanks!