Try exchanging the order of your individual Plots inside your Show and see how this changes. I remember that long ago Show would either use the first Plot's range or the last Plot's range and not correctly incorporate the other Plot ranges, but I don't remember whether that was fixed or is still a problem.
I haven't seen someone use a PlotRange->All at the Show level, but not inside the individual Plot level. Perhaps that is part of your problem.
If none of that easily and consistently fixes the problem then try explicitly giving a numeric PlotRange inside each Plot, make all those the same and make those just enough to contain all the Plots, not just the current one.