Music volume turning off when headphones moved around
Sounds more like a bad connector problem.

Try cleaning the headphone plug using a rough-ish cloth to clean up the (probably unseen) oxidation layer.

Spray the plug using a contact cleaner, then while it's not yet dried, plug it into the jack and do some left-and-right rotation. Unplug, and let the plug dry. Then replug, and do the rotations again.

If the above does not fix your problem, there's possibility that the solder contact between the jack and the phone's mainboard has cracked; you need to bring your phone to the service center (or someone skillful enough to perform cellphone repairs).