Both versions widen every span by five seconds either side, which is your
diagnosis and I think it is the right one. They differ only in how long the quiet stretch
is that fills them.
Why the last one went backwards. The version you rated ten out of eleven laid its
bed under the whole episode, so every rustle was covered — including the ones nobody
ever found. The next one only replaced the tight marked spans, so anything just outside a
boundary survived. The boundaries were never good enough for that, which is what you heard.
Widening costs nothing. The voice lives in its own stem and is never touched —
verified bit-identical in both versions — so extending the treated region only ever affects
the room. Five seconds either side is free insurance against a boundary being off.
A fills with a ten-second stretch of quiet room. B fills with one and a half
seconds — the short loop you found barely noticeable — placed the same way. Everything
outside the widened regions keeps the real room in both.
Coverage: episode 6 treats 41 seconds of 550, episode 5 treats 89 of 432.
nothing playing
Each clip now plays the whole widened region, so you hear the
run-in, the rustle and the run-out. Amber marks the ones that failed last time.