I installed volumio 3.887 on a sd card for my pi zero w.
I added the Music folder from my NAS drive, and all was well. the next day I wanted to add more music to volumio from my NAS drive, but as soon as I clicked on Update, the NAS drive became unmounted, and I can’t remove it to re add it.
Well i did add a new drive but that wasn’t mounted either.
This has happened to me a few times too.
Main volumio has a USB drive with the music
Second volumio connects to the NAS share on the first, works fine
Then occasionally it just disappears
Restart of the second volumio and rescan fixes it.