Problems reading the whole Nas

I have a Raspberry 3 B+ with the last version of Volumio and an Audiophonic 9038 i2s Dac. The system is connected to an Hd connected to the router. Volumio can see and mount the Hd, but scanning stops after 1000, 2000 or similar number of albums, without coming to the end. If I don’t fail, a couple of version ago I was able to scan the whole drive.
What’s the problem?

Tnx, Stefano