The SoundRecording composite in an ERN message is “Release specific”. 

This means that there is the possibility that some of the metadata for a recording might be different between different Releases — despite the recoding carrying one identifier. 

One example for this is the genre. The same sound recording may have a genre “Pop” in one Release and “Euro Pop” in another. 

Another example is the DisplayArtistName of a collaboration between two artists A and B, which may be “A feat. B” on A’s album but “B with A" on B’s.