Put sound in the packed container, and find the padding is a rate error

ROADMAP P6b, FINDINGS 67.  DLXP2: a 64-byte header and then groups -- one
audio lump of A sectors, then F records -- so record i is at
off_frm + i*rec + (i//F)*A*512 and lump k at off_aud + k*(F*rec + A*512).
Still no index and still none needed, which is the packed branch's whole
claim surviving the one change that could have ended it.  The player carries
the third term in six instructions once a frame and zero parsing, and 120 of
120 records are still pixel-exact off a real MB89352 volume with the
interleave in, against a silent control that says no picture byte moved.

The finding is what 65.3 called padding.  A lump is 7,168 B of SPACE; eleven
frames of audio is 7,161.4583... B, so the payload alternates 7,161 and
7,162 and the rest is zero.  A player that fed the chip the whole lump --
which is what "14 sectors every 11 frames" invites -- runs 0.09% fast, and
that is not waste, it is drift: 0.84 ms a group, 1.25 s of lip-sync over the
game's 22.8 minutes.  What a player carries is one accumulator,
acc += 11*15625; n = acc//24; acc %= 24, which is clock.i's shape for
clock.i's reason and the third time this tree has met the pattern.

The four ADPCM axes ride in the header as fields rather than a version
number, and the gate flips each one to prove they earn it: nibble order
-31.99 dB, delta formula -24.86, clamp 0.00, accumulator -0.49.  Nothing
parses a packed container, so the gate partitions the whole file -- 131
spans, no overlap, no gap -- and asserts what a cadence-blind player would
read: exactly records 11..119 wrong, and frames 0..10 identical either way,
which is how an off-by-one like that survives a rig that checks frame 0.

Wire 582.0 + 7.64 = 589.6 KB/s, 65.3's prediction to the tenth.

Green light ALL GREEN before (tmp/check_s35_start.log) and after
(tmp/check_s35_end.log), with the new stage in it.

Claude-Session: https://claude.ai/code/session_01194oWYW8DQXK1SZ2DnChW6

tools/analysis/30_packed_container.py

@@ -91,12 +91,20 @@ print(f"  round-trip: {d.nframes} records unpack and re-pack byte-identical")
 print(f"  index 0 (transparency key) used {zero} times; "
       f"index 255 (black) {black:,} times in the picture")
 
-kbps = d.kbps()
+# THE PICTURE'S wire, and it is the one this file is about. DLXP2 puts audio on
+# the same wire at a cadence (65.3, 67) and `d.kbps()` is both; what is asserted
+# here is that the PICTURE's share is still exactly geometry, because that is
+# 61.6's claim and a second stream is exactly the thing that could quietly
+# dilute it.
+kbps = d.video_kbps()
 geom = d.rec_bytes * d.fps / 1024
 if abs(kbps - geom) > 1e-6:
     fail.append(f"wire {kbps} != geometry {geom}")
 print(f"  wire {kbps:.1f} KB/s = {d.rec_bytes:,} B x {d.fps} fps. FIXED. A codec's "
-      f"bitrate is a lever and a literal frame's is geometry (61.6)")
+      f"bitrate is a lever and a literal frame's is geometry (61.6)"
+      + (f"\n  ...and {d.audio_kbps():.2f} KB/s of audio rides beside it on the "
+         f"F={d.cad_f}/A={d.cad_a} cadence, for {d.kbps():.1f} KB/s total "
+         f"(tools/analysis/34_packed_audio.py)" if d.has_audio else ""))
 print()
 
 # --- 2. the picture ----------------------------------------------------------