What do you mean by "does not support"? Does it not recognize/use this tag or does a tagged "album artist" cause some kind of problems?
In general the Album Artist issue is not simple.
Inside MC you don't actually need to tag it separately. By default a "various artists" album will automatically get the (Multiple Artists) value to the calculated "Album Artist (auto)" field and MC uses that value for grouping. The separate "Album Artist" field will not be tagged automatically. You can tag it manually if you want to override the default "auto" value. Check this link for more info:
http://yabb.jriver.com/interact/index.php?topic=59513.msg402038#msg402038 (Topic: Album Artist (auto)/Album - need basic explanation).
Regarding file tagging, MC tags the actual Album Artist field only if it has a value in the library. Unfortunately an "Album Artist" tag is not included in the ID3v2 standard. The program developers have introduced various ways to tag "Album Artist" to MP3 files. The two de-facto standards are to use the "TPE2" aka "Band/Orchestra/Accompanient" tag field and to use a custom TXXX Album Artist tag field. In order to support both standards MC writes both tags when the Album Artist field has a value.
If you really need to disable tag writing for this field you can do it in the field specific options: Tools > Options > Library & Folders > Manage Library Fields... - select "Album Artist" and uncheck "Save in file tags (when possible)".
If the car player has a problem with ID3v2 tags in general, you can set MC to write only the old and very limited ID3v1 format: Tools > Options > Plug-in Manager > Input > MP3 Plugin > Configure...
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Topic: How to Delete Albumartist (Read 2318 times)