I have had a blocked Eustachian tube for 3 months. Prescribed Nasal sprays, Antihistamines, decongestants to no effect. Also tried a Nasovent (Balloon). Good Luck with the Eardoc. Interesting concept - flimsy design - and it didn't work for me.
One thought crossed my mind, when you apply constant vibration to certain fluids it could have the food mixer effect, ie, instead of loosening it could make the fluid thicker(!)
Has this been taken into account ?