Seems 1/50 is anything between two internal parameters, an electronic shutter speed emulation parameter and some kind of darkening parameter, and perhaps the auto program adjusts that latter darkening parameter for fine-tuning but not the internal shutter speed parameter, the actual shutter speed is identical at the reported speeds of 40 and 50. If you shoot mainly on a 50, that will be about 1/45. Do you think as acceptable for avoiding the flicker?