Don't quite understand the obsession over 1/48 vs. 1/50. Back when I was working as a professional still photographer I had my shutter speeds calibrated by the legendary New York camera repairman, Marty Forscher and he explained to me what was within tolerance and what needed attention. The difference between 1/48 and 1/50 is insignificant.
1/48 = 0.020833333333333
1/50 = 0.02
The cameras you are comparing are probably rounding the shutter speed display differently.
[EDIT] When I switched career from still to motion picture I noticed that the "normal" 180 degree movie camera shutter at 24fps was 1/48 sec. while still cameras were calibrated in full stop increments: 1, 2, 4, 8, 15, 30, 60, 125, 250, 500, 1,000. See the rounding going on?