And how many times have you cleaned It? I remember this job very well, part of every new technicians routine in broadcast radio, especially because people smoked, and now people vape, it’s relevant again. Canford in the U.K. made a fake plug that had holes so you could pop it in, squirt the cleaning fluid in and spin, opening the contacts, and slushing the muck out.
As patch bays are passive devices, dirty contacts are inevitable, and if the worst is in the switching contacts, then you need to take them out and clean them. That is all DBX will do. Swabs, wipes, isopropyl and time. It’s not hard, just a pain, and you must label every cable or it becomes a nightmare. Your not supposed to put mics through patch bays, but I have done it a few times and although I can’t be certain, I wonder if phantom power tarnishes the contacts by some electrolytic action on contacts that might have humidity damped surfaces? They seem to need cleaning more often? Just an observation . I moved to XLR patches and they’ve always been fine and reliable. Line level patching is a hundred years old, so cleaning well understood. The technique of sticking a jack in and doing an in/out sequence as fast as you can, then a squirt, then repeat and repeat is daily duty for many studios. Contact cleaning is annoying.
if you are getting extra high levels, that’s not cleaning, they are being generated somewhere, so you have to be systematic in your fault finding or you will get in a real mess. No way you are getting phantom power into places it shouldn’t go?
it really just means starting with the source and hard wiring to designation. If that works, then replace the path to the patch, then from the patch until you tie it down. If you send the patch bay away, what if the fault is elsewhere?
