Hello. I recently bought an Olympus OM4 with a 50mm f/1.4 lens from an antiques shop. It is in very good physical condition and seems to work well mechanically, but there seem to be several electrical issues. The main issue is the shutter speed in Auto mode, which is significantly slower than the correct meter reading indicated on the LCD display. I have tried testing it to find a fixed pattern (a common error in the shutter speed - e.g. +2 stops) but it seems to vary from about +1 stop to +3 stops longer than the metered speed. Strangely, it is not a problem in spot metering mode - the shutter speed here is correct to the meter. The manual mode, of course, works fine. Today was the first time I noticed that the spot metering system was becoming temperamental. As I was testing the shutter speed issue, the spot metering suddenly stopped working - all of the associated buttons and memory levers did not respond. I later realised that the spot metering would only work when the lens switch (a conical button on the lens mount, below the red registration dot) was depressed by the attached lens, and this switch was temperamental. In theory, whenever the lens was removed, the camera would beep and the spot metering would be disabled. Unfortunately, the switch would often randomly disengage if the lens was touched or twisted, causing an erratic barrage of beeping and erroneously disabling the spot metering. Depressing the button with a fingernail (further in than the lens would) seems to create a more solid electrical connection, so I might find a means of fixing the button permanently. This video demonstrates the issue with the shutter speed.