avc audio quality regression

[ami_stuff]

decodes much better with 4.2.7

./ffmpeg_g -i 32khz_mono_56kbps.avi out3.wav
ffmpeg version N-109064-gc124981b79 Copyright (c) 2000-2022 the FFmpeg developers
  built with gcc 9 (Ubuntu 9.4.0-1ubuntu1~20.04.1)
  configuration: 
  libavutil      57. 42.100 / 57. 42.100
  libavcodec     59. 52.101 / 59. 52.101
  libavformat    59. 34.101 / 59. 34.101
  libavdevice    59.  8.101 / 59.  8.101
  libavfilter     8. 50.100 /  8. 50.100
  libswscale      6.  8.112 /  6.  8.112
  libswresample   4.  9.100 /  4.  9.100
Input #0, avi, from '32khz_mono_56kbps.avi':
  Duration: 00:00:30.08, start: 0.000000, bitrate: 212 kb/s
  Stream #0:0: Video: msvideo1 (MSVC / 0x4356534D), rgb555le, 320x240, 144 kb/s, 25 fps, 25 tbr, 25 tbn
  Stream #0:1: Audio: avc ([1][5][0][0] / 0x0501), 32000 Hz, mono, fltp, 56 kb/s
Stream mapping:
  Stream #0:1 -> #0:0 (avc (on2avc) -> pcm_s16le (native))
Press [q] to stop, [?] for help
Output #0, wav, to 'out3.wav':
  Metadata:
    ISFT            : Lavf59.34.101
  Stream #0:0: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 32000 Hz, mono, s16, 512 kb/s
    Metadata:
      encoder         : Lavc59.52.101 pcm_s16le
size=    1876kB time=00:00:29.98 bitrate= 512.6kbits/s speed= 947x    
video:0kB audio:1876kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.004060%

[Carl Eugen Hoyos]

Regression since 6ba0aa1770ba29eb4126c6a706f6b0cd3809648f

[Balling]

Wait a second. How is that possible? New lavu/tx is more accurate. But yeah, it does happen.

[Balling]

Cool ​https://patchwork.ffmpeg.org/project/ffmpeg/patch/20230805083259.24406-1-cus@passwd.hu/

[Balling]

It now decodes mostly the same, but some bytes are quite different like before there were 0xFF06 and now 0x0007. See f296c765905ca110a05d77a7e919d992800d2e11 and 2eb7df1cbd30d7c104face1ac93bc32aba070d53.