Studio Beats By Dr. Dre Not Working

Hi recently bought some beats by Dr.dre off Kijiji and they are acting kind of weird.basically when i plug them into my iPhone and play a song it works but when i turn the volume up to like 75% or higher they cut out and come back shortly and it keeps happening until i turn the volume down. The next problem is when i tap the headphones or kinda shake my head a bit they cut out but, i recently figured out that if i turn on the mute switch, and then turn it off the sound comes back. Also when it cuts out the song doesn't stop it just keeps going.i'm not sure if they are fake or not but i only got the headphones and wire from him so i wasn't able to look at the packaging and the batteries were not Duracell but they were in English so it wasn't from china and there's a serial number and signature. Any help would be greatly appreciated!

Added (1). And the batteries were not the same different brands.

Added (2). Thanks for your replies everyone but i just opened up the battery cover and replaced the batteries now they work fine, but thanks for your input!

I have real ones and they never do that. I would never buy beats online because they make really nice fakes

I'm not familiar with who/where you bought them from… If you are sure they are authentic then great but if not that might be the problem. I know popular brands with large price tags are often sold as replicas of lower quality. Its just something to look into

Are they authentic? When my heartbeats by lady gaga broke i called the customer service line and they had me ship them my old pair.about a week later they sent me a brand new pair.same company so call and see.