Yesterday I opened the BCL-9 cover as usual and now it refuses to close. The lever goes a little after the infinity mark and then it stops. I tried to wiggle it a little, upside down, to shake the lens, nothing. Gently tapping on the back of the lens while in this position the sound of a small spring vibrating can be heard. While in this half-closed position the closing "leaf" is not yet visible. Ever happened to anyone? Any ideas? I suppose it could be quite easy to disassemble and maybe fix it but it is still under warranty and I do not want to loose it.