# m4a files with hidden tags?
**URL:** https://community.mp3tag.de/t/m4a-files-with-hidden-tags/6733
**Category:** General Discussion
**Created:** [May 1, 2008, 12:40pm UTC](https://community.mp3tag.de/t/m4a-files-with-hidden-tags/6733 "2008-05-01T12:40:13Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@kael](https://community.mp3tag.de/u/kael)
#### Post date: [May 1, 2008, 12:40pm UTC](https://community.mp3tag.de/t/m4a-files-with-hidden-tags/6733/1 "2008-05-01T12:40:13Z")
When I convert m4a to mp3 files with iTunes 7.2 I noticed there seems to be a sort of hidden USER tag inside the mp3. I can't see it with mp3tag or Winamp. But when I use Gspot it says under the section User data/Metadata: [USER] 2Mh)2u. I have 4 such tags, each with other data.
Even after deleting all tags with mp3tag there is still 1 left.
Other mp3's made with lame don't have those USER tags.
I noticed that a m4a header also contains lots of other stuff not visible in mp3tag like the iTunes accountname, .... (I made it visible with Faad the m4a encoder [http://www.rarewares.org/aac-decoders.php)](http://www.rarewares.org/aac-decoders.php))
What are these USER tags for?
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### Author:  [@Florian](https://community.mp3tag.de/u/Florian)
#### Post date: [May 2, 2008, 1:46pm UTC](https://community.mp3tag.de/t/m4a-files-with-hidden-tags/6733/2 "2008-05-02T13:46:07Z")
Sorry, I really don't know and never seen such a tag.