Shuffle on album level

[PJVervoorn]

filename "NAS/Music" as the filter string

Hi Tim, that would, theoretically, be the same as having no filter; it would need to be:
filename “NAS/Music/Rock”
but unfortunately it doesn’t work anyway.

The quotes need to be straight double quotes. On my mac I have disabled smart quotes, so they are not replaced automagically.
You don't need to match from the start, so you can skip NAS/blah
I also found that the filter value can be used without the double quotes, even when it contains a / 
This will do what you want, unless you have more shares or directories matching Music/Rock

Code:

filename /Music/Rock/

This shows the different types of quotes