After I finally get a nice bag that fits all of my photo gear, I suddenly find that the lens on my Kiev 60 (a Volna 80mm) is having problems when adjusting the focusing mechanism... Sounds like stone or glass scraping or grinding, even clicking. I haven't messed with it since the discovery. It's profound since it has been operating just fine recently and in the new padded bag this week. What could it be? I really don't want to replace it or have to pay a lot to get it repaired... Thanks!