My setup:
Roon Core 1.3 (build 209 64-bit)
Roon version 1.3 (build 209)
Mac Mini Server (mid 2011) i7; OSX 10.12.3; 8Gb RAM
All music stored on 2 internal hard drives 1. in iTunes library on internal HD1 and 2. DSF files on internal HD2. No NAS.
Around 25.000 number of tracks including TIDAL tracks
Problem description: I had to restore a backup after my update to OSX 10.12.4 failed. I restored my backup from the Time Capsule in my network, not realizing this could corrupt my Roon database.