I have read for years about the joys of contact cleaner. (No, not contact lens cleaner.. I wear contacts, I know about that). I mean electronic contact cleaner. Earlier this morning, I was playing through my 1996 Carvin F150 power amp, when the fuse blew. Not sure what happened. I knew this amp had scratchy pots, so I headed off to Radio Shack and bought replacement 2.5A slow blow fuses.. AND contact cleaner! I have a Carvin DCM600 power amp also, which I bought used from eBay last year after selling my old standby DCM1500. The 600 was okay for a while, but then the bridged mode Speakon starting getting fuzzy and weak. The left and rights were okay, then they started getting fuzzy sounding also. Because this was a used amp, I started thinking the amp was going bad and I'd need to get it serviced. Meantime, my trusty old 1993 Alembic F-1X was getting very noisy and scratchy sounding.. a parallel development. I got back in today with the RS contact cleaner. I opened up both the DCM 600 and the F-1X, and shot the heck out of all the contacts and jacks with the cleaner. I also checked all the internal connector jacks for proper seating, and put the cases back together, racked it up, and played. WOW. It's amazing, kids. I heard the F-1X and DCM600 rack combo in full glory. No more crackling- at ALL. Just pure performance. I played a LONG time. I'm not sure I had ever heard the real sound of that preamp/amp. Excellent. Oxidation and corrosion are ongoing problems with electronics in real world environments. Exposed to humidity, oxidizing, and playing conditions, all our bass electronics will develop problems relating to the contacts. So.. don't do like I did and wait a long time after you buy gear to open it up and clean it with a contact / oxidation cleaning product. It literally can bring malfunctioning gear back to life. I'll do the F150 tomorrow..