iTunes/iMac question (again)!

Having got iTunes playing my NAS stored music, I came across a disc it can't find.

Info for track 01 says,  Where: file://localhost/Volumes/MasterMusic/Oldfiled, Mike/Crises/01 Crises.aif

One that works:- 

Where:/Volumes/MasterMusic/Music/Mike Oldfield/ etc/etc/

QUESTION is then .....     Where is this file://localhost ?  

iTunes11.1.4  OSX 10.9.1