Did you(in that post) also click on the (lightblue) link 'this thread' in the line:
(For some additional info on loading/playing subtitles perhaps also check
this thread.)?
If that information did not help you at all, maybe you could start by telling us the type of subtitles, the top two settings under (rightclick > Options > Preferences > Subtitles) and the 'Rendering mode' under rightclick > Options > Preferences > Video > Video rendering