Error in streamed MPEG4 handling - Movie.pm or Audio::Scan error ?

Looking at feasibility of an Accuradio plugins and was checking the
audio streams.
I've having a problem playing some MPEG-4 streaming URLs. Tests are on a
Ubuntu system LMS 8.3 (2Jan) 

It looks like a bug in either LMS MPEG-4 Handling of InitialAudioBlock
or in Audio::Scan

Example URL.
https://d1qg6pckcqcdk0.cloudfront.net/classical2/londonoratorysc_sacredtreasures_07_salvatormundii.m4a

When downloaded as a file, the file plays OK on both an Receiver (i.e.
faad MP4->Flc transcode) and a DAC32 (i.e. MP4->aac) 

When played as an URL
- no output on Receiver - faad (-q removed) produces an error -
Duration, speed and channel all are wrong.

Code:
--------------------
    
  Streamed input format  samplerate 22050 channels 0.
  - file info:
  ADTS, 1.000 sec, 16 kbps, 44100 Hz
  
  Error: Bitstream value not allowed by specification
  
--------------------


- DAC32 error  following error is logged 

Code:
--------------------
    
  [22-01-02 16:58:25.3427] Slim::Player::Squeezebox2::statHandler (156) Error: 7c:9e:bd:2b:52:94: Decoder does not support file format, code 0
  
--------------------


On examination an extra 4 bytes of zeroes had been inserted by LMS into
the created ADTS audio stream from MPEG-4 file.
It seems there is padding in the m4a file and so the value of "seek
offset" to start of audio and length of MPEG4 header are not the same. 


In Movie::findFrameBoundaries - Audio ::Scan is called on initial Audio
block of m4a stream.
Data::Dump::dump of variable $info (returned from Audio::Scan) 

Code:
--------------------
    
  [22-01-02 16:38:20.1771] Slim::Formats::Movie::findFrameBoundaries (198)  Dump of info from AudioScan do {
  require MIME::Base64;
  {
  audio_offset      => 22_092,
  audio_size        => 880_370,
  avg_bitrate       => 62_768,
  compatible_brands => ["M4A ", "mp42", "isom", "\0\0\0\0"],
  dlna_profile      => "AAC_ISO_192",
  file_size         => 22_116,
  major_brand       => "mp42",
  minor_version     => 0,
  mv_timescale      => 90_000,
  samplerate        => 22_050,
  seek_header       => MIME::Base64::decode("
  .
  .(deleted)
  .
  "),
  seek_offset       => 22_108,
  song_length_ms    => 224_351,
  tracks            => [
  {
  audio_object_type => 2,
  audio_type        => 64,
  bits_per_sample   => 16,
  channels          => 1,
  duration          => 224_351,
  encoding          => "mp4a",
  handler_name      => "Sound Media Handler",
  handler_type      => "soun",
  id                => 1,
  max_bitrate       => 37_608,
  samplerate        => 22_050,
  },
  { duration => 224_351, id => 1 },
  ],
  };
  
  
--------------------

Audio::Scan - the length of $info->{seek_header} is 22,100
Audio::Scan - audio_offset is at 22,092 but seek_offset to start of
audio is 22,108 

LMS seems to be streaming from end of MPEG4 header when it should be
streaming from seek_offset which is start of audio. 
Not sure if the error is in Audio::Scan or Movie.pm.

I'll try to come up with a solution but any suggestions welcome. I need
to check Audio::Scan documentation to see if the returned values are
correct and expected.


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