How do I use a referenced entity in a Views contextual filter? I'm building a media server for my university.   I have an "artist" content type for each performer, and then a 'track' content type for individual track (there are no 'albums', BTW).  For each track, you can select the artist in edit mode, using an Entity Reference.  So far so good!

On each Artist page is a block view with a table listing that artist's songs (the filter is 'show all tracks with a contextual filter of "artist").  Still good!

On each track page, I want to show "all tracks by this artist" as a table.   I've tried "artist" as the contextual filter, and even tried both "referencing entity" and "referenced entity" as relationships, to no avail.    If I put an artist NID in to the fixed value in the 'artist' contextual filter, it works fine.  But I'm pulling my hair out, trying to get the artist to dynamically be referenced by the block's contextual filter, using the tracks 'artist' entity reference.    

Am I missing something here?  It really seems like it shouldn't be that hard.    Thanks in advance!
For the curious, with Huelfe's help I solved it with a custom PHP code, in order to obtain the applicable NID for that contextual filter.  Seems like something that should be built in to Views already...!   I've successfully reused the string or several other projects as well.