Recently my 50/1.4 lens causes Err 01 consistently. This is communication error, the exit error message is this (just for the record: "Communication between the camera and lens is faulty. Clean the lens contacts." This happens from time to time with every lens, and cleaning contacts normally helps. The same for this one. But recently the lens became unusable. It autofocuses fine, but press the release, and I get this message. Contacts on the lens look fine, they show some wear, lens is dated 2003 or so. Cleaning sometimes helps, but after only one or two shots its errors again. I just wonder if anyone came across problem like this? Other lenses on this body work fine. I didn't see tis error in years, until recently.