Why won't my volume control work properly?

[AC Question]

Why wont my volume control work properly

Ive been using my samung earphones on a regular on my samsung galaxy, they work really well you can still get sound from them but for some reason whenever i press the pause/play button the volume goes up and when i press the - sign the volume does go down like its supposed to but for some reason when i press the + sign the volume also goes down please help!!