My ears "click" every single time I swallow, for years now.
It never really worried me untill I noticed in the past few years that my ears ring a lot. High pitched buzz, sudden fading out of frequencies for about 10 seconds, ringing. This can happen up to 5 times a day, and at LEAST 1 time every day.
My ears also hurt badly when I swim for long periods of time- is this swimmers ear?
The ENT insisted that I stop smoking when I take the allergy meds he prescribed, as it would render them useless. Of course, I didn't take them, and decided to get some other opinions first. I never had allergies, and don't get any of the nasal, headache problems usually associated w/ allergies or sinus problems. I don't doubt that the cigarettes are aggravating it.
The hearing test was "pretty much normal" (I think my hearing is terrible) except that the muscle that contracts at loud noises doesn't reopen properly. I was told not to worry about it, but it scared me.
Desert Rose is right, look in to TMJD - it may be helpful to you. Grinding and clenching can be a component of TMJD but not always. The theories behind why it happens are complex, and there is a lot of contention about it. I can't really begin to try and explain it all, but there is loads of info on the tmjd board on here. Many people think 'I don't have a problem with clenching/grinding/my jaw etc'... so I don't have that. It is totally possible to experience the problem only as ear problems or dizziness (it is referred to as 'the great imposter') and can often mimic ear disorders as the problems can be referred from the jaw to elsewhere in the body. Muscular spasms and swelling caused by upset to the jaw causes these other symptoms. And yes, tmjd can often be a cause of unexplained (by ENT doctors) hearing loss. Sadly this is an area about which many ENT's are not informed enough.
I don't know if you have this, but it doesn't hurt to do a bit of reading and look in to it. Try putting the word 'ears' or 'tinnitus' (ear ringing) in to search on the tmjd board.