Shuffle on album level

[Nutul]

You are introducing too many fancy changes...
Start from scratch:
1. ensure you know (yeas, ensure you do know it) the path you want to mount as a SMB share
2. clear any SMB share on your Pi, and shutdown + boot (shutdown does not plainly mean unplug, but shutdown command)
3. create a new SMB share uing the path above, specify a known name for it, verify it works.
Then do one more shutdown + boot of the Pi. It should remount everything.
Use machine names, possibly with ".local" appended to them, and not IPs, unless they are static, of course.
It's been, and it is, working for billions of people; it should for you too.

I’m not introducing any changes, fancy or otherwise.  I have three sources mounted. Their paths are:

192.168.0.157/Public/Music
192.168.0.157/Public/Classical
192.168.0.157/Public/OtherStuff

Everything works fine except for all attempts to restrict the shuffle to one particular folder on the NAS, which is 192.168.0.157/Public/Music.

With "fancy" I meant the last minute change in the shared folder's name... nevertheless:

1. you need ONE SMB mount, at 192.168.0.157/Public
2. Name it whatever you like, 5N2Music is meaningless to me, but surely isn't for you, so be it
3. Verify that you can have that mounted on moOde
4. Do a library rescan at this point, as probably it is a little bit cluttered...

Now, in the filter, specify NAS/5N2Music/Music, OR NAS/5N2Music/Classical OR NAS/5N2Music/OtherStuff

Until you cannot confirm the mounting of 192.168.0.157/Public with 5N2Music as its name, scanning the library, and verifying that ALL the music contained in its three sub-folders (Music, Classical and OtherStuff) is visible by moOde, there is no meaning in testing anything else.

HTH