I've just installed with no problems Subsonic 5.2.1 (build 4428) on my new home server running Ubuntu Server 14.04.2.
I've just put few albums on my server yet (8 albums), Subsonic indexed well my songs after I set the folder configuration.
But I don't know why, Subsonic don't shows my songs... It's very strange.
Look at this screenshot :

At the bottom left, we can see that Subsonic says I have 8 artists and 8 albums, 105 songs, for 729,8 MB.
But I can't see (and play of course) them. What is wrong with that ??
My songs are organized like that "Genre>Artist>Album>Songs" (but I also tried in "Artist>Album>Songs" but nothing changes).
In my previous version of Subsonic (4.X) this was not a problem.
Do you have an idea of what's happening ?
Thank you !