Hi there. Humming in the head could be due to tinnitus or ringing sensation in the ears. The causes of tinnitus are ear wax or foreign body in the ear, loud noise exposure, drugs like aspirin, meniere’s disease, brain aneurysm or tumor. Consult a neurologist for a detailed clinical examination, audiogram, auditory brain stem response and CT/MRI as deemed relevant by the otolaryngologist. Therapy would be guided by the diagnosis. Take care.
If it's located more directly in the ears, it is tinnitus.
Many things.
Tinnitus is one of them. Is this all you experience?