Audirvana Mac Version 3.5.32 (3562)
macOS 10.15.3 with 32768MB RAM
I have huge (approx 10000 songs each) playlists based on folders on Qnap NAS drives (mapped as SMB drive).
Steps to repeat:
Select few songs (mostly based on subfolder (an album)) and play them. Or select one, following ones are in the queue. Prune the queue, go back to playlist.
Some of the songs disappeared - are missing. Sometimes it helps to switch between playlists, sometimes even restart of the app does not help and these songs are not in the playlist anymore.
This has bugged me since the 3.5 audirvana version came out, but after upgrading macOs to Catalina it is almost unbearable. The only workaround I have is to work directly with library - but it is almost impossible because it is really huge, tens of thousands of tracks. And search is broken either - sometimes songs which are in one folder (which is one album in my case) are not searched as an album, but each songs or couple of songs each forming its “own” album. So search is mostly unusable. The reason might be that tags on these songs are not done properly or missing completely. But the app might be intelligent enough to consider songs in one folder to form an album. Or at least there might be a setting for this.