My thoughts follow your comments below.
After stepping back from the coal face it suddenly became obvious how the different m3u files are created, at least this is what occurs on my system which has LMS installed on a server and MediaMonkey installed on separate PCs.
Yes, this is the same as my situation.
If you select "File > Export to Playlists" the "Save As" window opens to the file location of the first track in the playlist. The file location address is dependent on the address of the scanned music folders in MediaMonkey. If you scanned from the network address then it opens to the network address of the file. If you scanned via a mapped drive then it opens to the mapped drive address of the file.
All consistent with my understanding and experience with MM.
If you save to the location as suggested by the "Save As" window or any location below the parent music folder, then the music file addresses in the m3u file will be ..\sub-folder\<Artist>\<Album>\<Title>, the double-dots reference the parent directory or folder, in my case "Music".
This is where my experience differs for yours for some reason. On the vortexbox, my parent music folder is /storage/files/music. (Note: Here I am specifying the actual directory on the linux-based vortexbox rather than the UNC address). Folders that are subordinate to this are “flac”, “mp3”, “playlist” and “wav”. I save the M3U file to the “playlist” folder and MM always generates a full pathname rather than the relative pathname in the manner you describe above. What you say above makes complete sense; it’s just that MM is behaving differently in my case.
I save my playlists to "Playlists" a sub-folder of "Music".
Exactly. I’m doing the same thing. I store to /storage/files/music/playlist.
If you decide to save via a different path, say the scanned directory in MediaMonkey is the mapped address and you save to the same location via the network directory then the music file addresses in the m3u file will have the full path of the file e.g. X:\Music\sub-folder\<Artist>\<Album>\<Title>. Note: The full path is not the network addressing as expected but the full path of the mapped drive address.
This is an area of uncertainty for me. I do not recall where MM first suggested that I store the M3U file. I seem to remember that I had to explicitly navigate to the Vortexbox (via the Save As dialog) to select /storage/files/music/playlist. (but of course using the UNC equivalent on the windows box).
LMS or Squeezebox devices can read the m3u files that have the ..\ prefix for the music file addresses, provided Squeezebox and MediaMonkey are referencing the same music starting at the same parent directory or folder, in my case "Music".
This is consistent with my experience. My M3U files only have relative paths and the LMS picks them up just fine.
It is helpful that the "Playlists Folder" in LMS > Settings > Basic Settings is the same playlists folder that MediaMonkey accesses.
On my vortexbox, the “Playlist Folder” (via Basic Settings) is set to “/storage/music/playlist”. I’m not exactly sure how LMS works but I cannot write to that folder. LMS only gives me write permission for content under/storage/files. I assume that when the LMS is reading files under /storage/music, it’s referencing links back to files under /storage/files/music. Not sure why it’s done this way… I cannot access /storage/music/playlist directly from MM. When I try, VortexBox denies me access. This is consistent with documentation I’ve reviewed.
Creating m3u playlists in MediaMonkey with the ..\ prefix is the preferred approach if you wish the Squeezebox system to read the same playlists or wish to use the same playlists in another location. I take my music to work on an external hard drive. On the hard drive I keep the same folder/file structure for my music files as I do at home i.e. Music\sub-folder\<Artist>\<Album>\<Title>. This enables me to use the playlists created at home at work on MediaMonkey as the m3u files only list the address of the music files starting below the parent folder "Music". I presume the programmers of MediaMonkey have taken the approach of creating ..\ addresses for maximum use of the m3u files as described above.
This makes complete sense to me. Relative pathnames equate to portable playlists, which is what I don’t seem to be able to produce. What’s very interesting is that within the LMS web interface, I’m able to change the location of the playlist folder on the basic settings page. When I click the browse button the subordinate folder named “files” under storage (i.e. /storage/files) isn’t even listed as an option in the folder selection tree. When running, the LMS on the vortexbox apparently doesn’t want to know about anything under /storage/files/music. /storage/files/music is the parent folder that I must use from within MM to copy over files and write playlists, but operationally, LMS only knows about /storage/music. I assume there is a link (as in linux “ln” linking) between /storage/files/music and /storage/music.
I’ll have some time in a bit to look at what Lowlander provided and see if I can address this problem. If I’m successful, I’ll circle back to let you know what I learned.