In my previous job, like 7 years ago, I used headphones too and my boss once called me to his office and forbidden listening to music explicitly. I tried to explain and ask for reasons and he just told me he didn't have to explain anything. A couple months after I applied for a new job and entered an environment where everyone used headphones to keep them concentrated to their work and the company even bought the headphones on request. And guess what, all the good developers left sooner and later too.
Managers like this are just morons, get off if you can.
