My brain finally remembered something I had come across about ears, and after searching in various places I found it in Erica Verrillo's e-book on ME/CFS. Unfortunately it doesn't seem possible to cut and paste text from it, so I will have to type it. Apologies if I make any mistakes.
"The left ear, in particular, seems to be susceptible to itching, which, because of its location deep in the ear, cannot be relieved. The itch and occasional accompanying pain do not, in most cases, signal the presence of an ear infection.
The likeliest source of the itch is lymphatic fluid congestion. The lymph system drains at a point just above the left collar bone. If the fluid backs up, it can produce swelling along the left side of the neck, left-sided jaw and molar pain, and itching in the left ear. In some cases Candida overgrowth is also implicated..."
The book also refers to sinus congestion causing muffled hearing. It also says that tinnitus can be caused by blocked Eustachian tubes, and that people with allergies get tinnitus during the 'allergy season' (by which I presume is meant the hayfever season).
There is a whole section on tinnitus, I really do recommend the book!
It is my right ear that is currently itching...