Playlists and NAS

My setup is the following: I have two instances of Volumio (“upstairs” and “downstairs”) and my music library is on an external hard drive attached to “upstairs” via USB. This gets automatically shared over the network and acts as a NAS for “downstairs”. This works fine, except for playlists. I have quite a few long (several 100s of items) playlists that I copied over from “upstairs” to “downstairs” and edited so that the URI’s point to the correct location. Whenever I try to play one of them though, the GUI freezes for a very long time (about half an hour!) before playback starts. During that time, each song generates two entries to the log of the form

info: Adding Item to queue: music-library/NAS/Upstairs/Music/Path/To/Song
info: Exploding uri: music-library/NAS/Upstairs/Music/Path/To/Song

The problem is that the ‘exploding’ part takes about 6-7 seconds for each song, which quickly adds up to insane amounts of time! Am I doing something wrong or is this a bug in Volumio?