do you cough anthing up, if not and you have a crackling sound and pain in that area you might have plurasy...quite often as a result of cold or chest infection. A simple spirometer test done in the surgery could diagnose any asthma type problems if that is a worry to you. There are many meds a GP could try you on if anything is found.
Good luck with the pulmonary specialist, thats the way to go.
P.S. My lung X-ray is clear as well. Asthma is associated with lung inflammation which is too minor be seen with X-rays (but major enough to make one miserable).
You should definitely see the pulmonologist. I've had that noise for a year by now, and it's been diasgnosed as adult onset asthma (I was 29 at the time) but I also have a set of other pulmonary symptoms, like titghtness and shortness of breath, which you don't mention. My asthma started as a resporatory infection.
I forgot to mention that I had no cough when the Doctor listened to my lungs, which is why I'm thinking asthma.
severe*** sorry about that... the pain was probably unrelated anyway.