iPhone headphones magnetic?

Has anyone else noticed that when you bring the right and left headphones near each other SLOWLY, with the speaker sides facing each other, you'd feel a magnetic push? The two headphones will repel one another. Just as if you were to bring two positive ends (or two negative ends) of magnets together.

Is it normal to have this magnetic force inside headphones? And if so, is it safe??? I can't imagine wearing 2 tiny magnets right next to your brain continuously would be safe?

Thanks to whoever that can shed a light!