Most definitely Ringing in the ears is what is known as TINNITUS... have it checked out medically if it is a problem for you.
http://www.medicinenet.com/tinnitus/article.htm
But to believe it's "someone" or "something" trying to contact you? Nonsense. Just speak to my face, or send me a letter, or even telepathic thoughts, that will do.
One of the most common causes of tinnitus is damage to the microscopic endings of the hearing nerve in the inner ear. Advancing age is generally accompanied by a certain amount of hearing nerve impairment, and consequently tinnitus.
I have known friends and family who have worked in factories where machinery noise is loud, and after years, it does do damage to the hearing nerves. And most definitely I've observed people as they grow older have hearing problems including tinnitus.