Mirror modifier creates an object inside another Mirror modifier creates an object inside another.
I need a Mirror modifier to correctly create mirrored object.
How to fix this?
This screenshot shows my problem. Mirrored ear piece spawns in original object.

I need ear piece to be mirrored is the same place but on the other side.
You can mirror around a different object. For example if you select the headphone band as the mirror object it will use that to mirror around instead of the origin of your object.   If there is nothing handy to mirror around create an empty and put it in the midpoint of where you want to mirror.  In your case I would imagine the headphone band would work for you as the mirror object.