I'm currently setting an AVPlayerItem's externalMetadata to have its, title, artist, and thumbnail image show up in the iOS player (shown in Lock Screen and control center). Presently, the title and thumbnail are working just fine when I set the AVMetadataIdentifier.commonIdentifierTitle and AVMetadataIdentifier.commonIdentifierArtwork identifiers inside my AVPlayerItem's externalMetadata array. However, setting the AVMetadataIdentifier.commonIdentifierArtist property is not filling that value in when I look at that iOS media player. The item is played using an AVPlayerViewController, which handles setting the MPNowPlayingInfoCenter, which I'd like to keep that way rather than setting the NowPlayingInfoCenter values manually. Is there an identifier that I should be using?