Straight from the horses mouth (so to speak :-) HERE IS THE DEFINITIVE ANSWER which will hopefully put an end to all the highly contentious debate which was inevitable given this threads flame-worthy attention grabbing title !!!
"Fortunately the USPTO has made the proper investigations and has reduced strongly the claims of this patent that was initially reusing public domain ideas.
It is basically limited to the exact proxy type Pure Music is using (proxy file with a silent block of the exact duration of the original file). Thus Audirvana Plus is NOT infringing this patent."