From what I can gather reading some of these PCSSB files they just seem like a bunch of separate FSB3 archives concatenated together.
But an oddity that I noticed is that for each .wav file in a PCSSB file the filename appears twice, in two FSB3 archives that are back to back. The second just seems to be a copy of the first but cut off at an early point.
I've attached some sample files so you can see what I mean.
Does anyone know why the developers might have done this and what purpose this might have? Only thing I can think of is padding or some sort of alignment thing, but then why not just pad with 0s instead?
PCSSB Samples.7z