I have discussed this in depth with numerous docs (this is the reason for going to an ENT and Neuro). My neurologist has ruled all of the possible causes you mentioned above except the blocked Eustachian tube, which my ENT had already ruled out. So.... no answers, just alot of noise and frustration.
Well, if Meniere's disease is ruled out, then the symptoms (tinnitus, vertigo and facial numbness) could be due to acoustic neuroma (a benign tumor of the eighth cranial nerve), TMJ, pinched spinal nerves in neck, blocked Eustachian tube or trigeminal neuralgia. Please discuss this with your treating doctor. Take care!
The medical advice given should not be considered a substitute for medical care provided by a doctor who can examine you. The advice may not be completely correct for you as the doctor cannot examine you and does not know your complete medical history. Hence this reply to your post should only be considered as a guiding line and you must consult your doctor at the earliest for your medical problem.