The site offered by Xrun. is helpful. If your RH has been running high (>80 RH), you probably have a mold problem. Inspect your gars for molds, separate the contaminated from the non-contaminated (I would put the suspected non-contaminated in quarantine for a couple of days, e.g. sealed baggie in refrig or seperate humidor), and throw away the comtaminated gars (ouch!). Get new Humidifiers, and clean out the contaminated Humidor as directed in the above site.
As a suggestion, what E-Chick said may be the only definite solution because mold problems once they start are difficult to fully eradicate. Mold spores being microscopic are difficult to diagnose unless you microscopically inspect your Humidor and cigars.
Hope you have a small humidor, and the casualities are few.
Ed