Another probable reason is vascular tumors sometimes called glomus tumors or paragangliomas.
These types of tumors normally develop in the middle of the ear and may produce a pulsating in ear symptom. These are not life-threatening though but can cause pain since they are in the most sensitive area of the ear.

The advantage is that they are not tied up to any brand. They are usually well versed with the latest innovations in the field and can provide you up to date information on the devices from various manufacturers too.