I have an RSM191 that has started to make its own noises. It sounds like a slow moving creature crawling over the capsule, rather like having oil dripped in the ear canal (those of you who have ever had this should know what I mean). The sound happens irregularly - once every 10 - 20 seconds or so, and lasts for about 2 seconds at each instance. The intensity varies over time; at its worst it is activating the limiters when on high gain. I power the mic through the mixer (not off the matrix box battery) and the noise seems to diminish after 10 minutes or so. Though I haven't submerged the mic, nor do I live in a particularly humid place (though it is England) could this be the effect of moisture somehow getting in?
Another clue may be in the 7 pin connector, which seems a bit more sensitive to movement than it should, even in the Rycote basket. Wiggling the cable, or tapping the tail of the mic sounds like a poor connection rather than someone tapping the mic. Maybe there are two things wrong with it.
Any ideas on what I could do to diagnose this better and resolve the problem?

Thanks,

David