• excessive ear wax (cerumen)
• ear infections
• damage to the ear drum (tympanic membrane)
• Eustachian tube dysfunction
• excessive noise exposure
• sensorineural hearing loss (nerve damage)
• cervical neck disease
• ear trauma
• aging
• temporomandibular joint dysfunction (TMJ)
• Aspirin
• increased intracranial pressure
• head trauma
• Meniere's disease
• ******************
• acoustic nerve tumors (acoustic Neuroma)
• brain tumors
• advanced syphilis

Conditions below the stars are rare causes of tinnitus.