Album Artist Problems Flac - Mp3tag - M4A - IPOD

My main music library is in FLAC. I have recently gone through the 20,000 files fixing all the tags. However when I have converted these files to M4A into iTunes the album artist is incorrectly displayed in some instances.

What seems to have happened is there are now two different 'ALBUMARTIST' tags in the M4A file.

How can I resolve this so that:

i) only the correct 'ALBUMARTIST' tags in the M4A file is used by iTunes
ii) future conversions from the FLAC files generate the correct tags

In addition, track numbers on the FLAC files don't always convert into the M$A files.

What is the difference between those files that did as you wanted and those that didn't?

Thanks for the reply

In the Flac File, for example, it will say:

Album Artist:The Beach Boys

In the M4A version it says: Album Artist: Beach Boys\\The Beach Boys

(That is when viewed in Using MP3 Tag)

In Itunes Album Artist is displayed as: Beach Boys

How does a program know that it should cut the "The" from an artist name?
Could you check the original file in the extended tags dialogue and also the settings for field mapping?
Also, I am not quite sure if you have ID3 tags and FLAC tags simultaneously in the file. The Flac file should have only FLAC tags, no ID3 tags.

No ID3, only FLAC tag.

In the extended tags it says:

Album Artist: Beach Boys
AlbumArtist: The Beach Boys
Artist: The Beach Boys

How do I check settings for field mapping?

See Tools>Options>Tags>Mapping
Anyway: you have 2 fields for more or less the same contents: %ALBUM ARTST% and %ALBUMARTIST%. The correct field in MP3tag would be %ALBUMARTIST% only.
I would filter for files with %ALBUM ARTIST% with
and then see how to merge this field with ALBUMARTIST and then remove the field ALBUM ARTIST.

Great - thank you.