Replace all Album Artist with Artist

My player seems to look at album Artist instead of Artist.
How do I replace every Album Artist Field with the Artist Field?
Thanks!

I do that a lot and have an action for it:

Name of action group: Artist to AlbumArtist

Action #1:
Action type: Format value
Field: ALBUMARTIST
Formatstring: %artist%

Action #2: OPTIONAL
Action type: Remove fields
Fields to remove (semicolon-separated): ARTIST

Thanks! I assume Action 2 blanks the Artist Field? Is that necessary? Can the Action apply to all files in a folder?

I should have labeled the second action as optional. You may want to remove it if you don't have any players that will try to display the equal fields twice. I had to use this WINAMP function to avoid that:

$IfStrEqual2(%artist%, %albumartist%,,[%artist% - ])

This functionality seems to be built into foobar2000.

Actions apply to selected files, so only select those with blank or erroneous ALBUMARTIST fields.