Tinnitus Low Blood Pressure

Why does low blood pressure cause tinnitus?
Yesterday, as i got up from my bed i got light-headed and i know it was from low blood pressure from getting up to fast (postural hypotension) but i also got a loud hissing sound (tinnitus) in my ear and i never ever have gotten this before when i get lightheaded i usually just get tunnel vision. Why did i get this hissing sound? How does low blood pressure effect the ears?
I think it could be related to blood flow because I also have low blood pressure and tend to faint a lot and I hear it every time I’m about to pass out. So you probably heard the blood flowing.
According to this article its because your ear is not getting enough blood flow therefore it cannot function properly.
http://tinnitusonline.blogspot.com/2006/09/low-blood-pressure-and-tinnitus.html
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