[2683] m4a multiple artists stored in single atom not recognized

[LMan]

Apparently, storing multiple "artist" tags in multiple atoms was common, but it atually goes against the m4a specifications. That's why tagging softwares (including mp3tag) recently started supporting storing multiple "artist" tags in a single atom instead.

This "single atom" variant is expected for instance by taglib, but not yet recognised in AIMP, which shows only the first artist.

I've attached 2 examples, maybe you can have a look.

Many thanks and keep rocking 

[Artem]

but it atually goes against the m4a specifications

Can you send to me a reference to specification about that?

[LMan]

Maybe I shouldn't have asserted it in the manner I did, however I think it's this passage:

"If grouping_type_parameter is not defined for a given grouping_type, then there shall be only one occurrence of this box with this grouping_type."

https://b.goeswhere.com/ISO_IEC_14496-12_2015.pdf

However I'm certain you know to interpret this better than I do. Specifications aside, it would be cool if AIMP was able to read that variant to improve compatibility with the different tagging sources.

[Artem]

But this for grouping, not multiple tag fields

[LMan]

All right Artem, you certainly know very much more about these things than I do.

I thought it might be a good idea to support the single atom variant, as it's the only one some other softwares like Navidrome accept. However if it's unreasonable effort I understand if you don't want to do it, all good.

Thanks for your time and looking into it!
Cheers

[sveakul]

Because it uses AAC for compression maybe try updating bass_aac.dll to 2.4.7.0?  That one was released July 25, 2025 after almost a year between last version (2.4.6.3).

[Artem]

Because it uses AAC for compression maybe try updating bass_aac.dll to 2.4.7.0?

It not related to tags recognizing