Hi, I just bought a used P20/1.7 first version on ebay. I was worried about the slow focus performance and I took a couple of tests this evening in very low light, like f1.7, 3200iso, 1/10s. When you have a strong contrast it locks almost always and immediately. When the contrast is mild it often hunt forever. The AF sound is ugly. Anyway, the problem is that after a few seconds, like 30 to 60, it completely freezes: AF does no longer work, neither aperture change and I cannot even turn off the camera. The only way to unfreeze it is to press the lens detach button to reset the lens. Ever heard about it? Before returning it is there anything I can do to try to fix it?