A little bit of crackle when you squeeze a cigar is, IMO, a good thing as it indicates that the cigar isn't too wet. A lot of crackle and cracking wrappers usually indicates that they are too dry. If such is the case, no need to worry, once you stabilize your humidor, they will come back to normal in time.
Assuming that you have tested your hygrometer for accuracy and it is reasonably accurate and that you have the proper amount/volume of humidification elements for the size of your humidor, your humidor needs to be checked for leaks. Once you have found and repaired them, or replaced the humidor if no other solution is possible, your humidity should be more constant and you'll get a better idea of how your cigars are smoking.
Link:
How to salt test your hygrometer for accuracy