Why is my iPhone 4 acting weird with music?

So when i go to the gym i listen to music. When i hear a song it fast forwards by itself and skips to the next song and then it pauses, it happens sometimes. Or when i'm listening to a song it presses Voice Control by itself. What is it?

You might want to make sure that you don't have "Shake to shuffle" on because movement of your iPhone can trigger shuffling with that feature. With the Voice Control problem I would check to see how tightly your iPhone is being held. This could also be a technical problem, but first check to see if the home button is being pressed or held. (That's how you turn on Voice Control) If it's not purely physical, it's unfortunately technical. IPhone 4's are not the newest phone so it could be a problem with age. Or sometimes there's songs that have messed up coding and mess up your phone/ device. However, the most common technical problem is when a phone has too much data on it and can't take in anymore such as pictures or in your case, songs. You only have a certain amount of gigabites on your phone and if you have used all of them up, you can't do anything and your phone is very slow. Other signs of too much data is when you are taking a video, you can't stop it from taping or recording