Audio glitches in tagged MP3 files

[GoogleCodeExporter]

When using mutagen to tag MP3 files, I'm seeing audio glitches at the beginning 
of some tagged files.

MP3 files are generated by Sorensen Squeeze from original edited WAVs

- File 1 is 224KB, File 2 is 1.7MB
- Copy and tag both files with a title tag.
- File 2 will have an audio glitch/jump in the first second 

There seems to be a correlation between length of MP3 file and the glitch 
occurring - it seems to be for files with length of 1MB and over.    

Mutagen inspect shows the following for the files

    mutagen-inspect 1.mp3 1_tagged.mp3 2.mp3 2_tagged.mp3 
    -- 1.mp3
    - MPEG 1 layer 3, 48000 bps, 32000 Hz, 37.28 seconds (audio/mp3)

    -- 1_tagged.mp3
    - MPEG 1 layer 3, 48000 bps, 32000 Hz, 37.28 seconds (audio/mp3)
    TIT2=title for file 1

    -- 2.mp3
    - MPEG 1 layer 3, 48000 bps, 32000 Hz, 298.07 seconds (audio/mp3)

    -- 2_tagged.mp3
    - MPEG 1 layer 3, 48000 bps, 32000 Hz, 298.07 seconds (audio/mp3)
    TIT2=title for file 2

python version 2.6.8, and mutagen 1.20 installed in venv with pip.

I've attached the original files for reference, as well as the script used to 
generate the tagged versions.

Original issue reported on code.google.com by rob.mcha...@somethinelse.com on 27 Jul 2012 at 12:04

Attachments:

• test.py
• 1.mp3
• 2.mp3
• 1_tagged.mp3
• 2_tagged.mp3

[GoogleCodeExporter]

The checksum of the parsed mpeg frames is the same for me using mpg123 and 
GStreamer mpegaudioparse.

I guess there is a problem with your player.

Original comment by reiter.christoph@gmail.com on 27 Jul 2012 at 1:47

[GoogleCodeExporter]

Thanks for your help Christoph,

I've tried on iTunes and preview (on mac) so far - I'll give it a go on another 
player/platform to see.

Could you hear the glitch at the beginning of 2_tagged.mp3 when listening with 
mpg123/GStreamer, or does it play exactly like 2.mp3 for you?

Cheers, Rob.

Original comment by rob.mcha...@somethinelse.com on 27 Jul 2012 at 2:36

[GoogleCodeExporter]

It plays exactly like 2.mp3.

Which iTunes version?
Does iTunes display the tags, and does it change after you edit tags with 
iTunes?

Original comment by reiter.christoph@gmail.com on 6 Aug 2012 at 5:04

[GoogleCodeExporter]

If you have any further information, please post here or open a new report.

Original comment by reiter.christoph@gmail.com on 26 Nov 2012 at 10:40

• Changed state: Invalid