I am having an issue with playlists. I sync content from my PC using MediaMonkey and it uploads playlists as M3U files. Until I got my external DAC, PowerAMP had no problems playing those playlists and can still play them without issue using the DAC. Once I got the DAC and started using USB Audio Player Pro, I found that the playlists had songs that wouldn't play. However, I can play those songs by going directly to the folder containing them, or using PowerAMP. Looking at the metadata for the songs that won't play shows that USB Audio Player Pro can see the file, but many fields are listed as zero.
Since this playlist is large, I tried to attach the M3U file, but the forum software wouldn't allow me to attach it. I opened the file in Notepad and are copy and pasting the contents. I double checked the file locations and they are there and can be played in their directories, just not in the playlist using USB Audio Player Pro.
\Music\Nobuo Uematsu\Distant Worlds II- More Music From Final Fantasy\01 Nobuo Uematsu - Prelude (FINAL FANTASY SERIES).flac
\Music\Hitoshi Sakimoto\Final Fantasy XII Original Soundtrack Limited Edition\03 Hitoshi Sakimoto - Opening Movie (FINAL FANTASY XII Theme).flac
\Music\Hitoshi Sakimoto\Final Fantasy XII Original Soundtrack Limited Edition\17 Hitoshi Sakimoto - The End of the Battle.flac
\Music\Hitoshi Sakimoto\Final Fantasy XII Original Soundtrack Limited Edition\18 Hitoshi Sakimoto - Ending Movie.flac
\Music\Angela Aki\Kiss Me Good-Bye\04 Angela Aki - Kiss Me Good-Bye (Ft. In Final Fantasy XII).flac
\Music\Nobuo Uematsu\Final Fantasy, Vol. 9- Piano Collections\14 Nobuo Uematsu - Melodies of Life.flac
\Music\Nobuo Uematsu\Final Fantasy IX Plus\18 Nobuo Uematsu - Birth of The New Queen.MP3
\Music\Nobuo Uematsu\Final Fantasy S Generation\12 Unknown - Unrequited Love [Piano Version].mp3
\Music\Nobuo Uematsu\Final Fantasy S Generation\15 Unknown - Behind the Door [Original Soundtrack].mp3
\Music\Nobuo Uematsu\Uematsu's Best Selection- Music from the Final Fantasy IX Video Game\03 Nobuo Uematsu - Sky of Alexandria.MP3
\Music\Nobuo Uematsu\Distant Worlds II- More Music From Final Fantasy\04 Susan Calloway - A Place to Call Home - Melodies of Life (FINAL FANTASY IX).flac
\Music\Nobuo Uematsu\Final Fantasy VIII Piano Collections\02 Shinko Ogata - Eyes On Me.flac
\Music\Nobuo Uematsu\Distant Worlds- Music From Final Fantasy\02 Nobuo Uematsu - Liberi Fatali (Final Fantasy Viii).flac
\Music\Nobuo Uematsu\Final Fantasy VIII Original Soundtrack\12 Nobuo Uematsu - Overture.MP3
\Music\Nobuo Uematsu\Distant Worlds- Music From Final Fantasy\05 Nobuo Uematsu - Don't Be Afraid (Final Fantasy Viii).flac
\Music\Nobuo Uematsu\Final Fantasy, VIII- Fithos Lusec Wecos Vinosec - The Orchestral Soundtrack\11 Koji Haijima - The Oath.flac
\Music\Nobuo Uematsu\Final Fantasy, VIII- Fithos Lusec Wecos Vinosec - The Orchestral Soundtrack\04 Nobuo Uematsu - Balamb Garden.flac
\Music\Nobuo Uematsu\Final Fantasy VIII Original Soundtrack\20 Nobuo Uematsu - Julie.MP3
\Music\Nobuo Uematsu\Distant Worlds- Music From Final Fantasy\04 Nobuo Uematsu - Fisherman's Horizon (Final Fantasy Viii).flac
\Music\Nobuo Uematsu\Distant Worlds- Music From Final Fantasy\10 Nobuo Uematsu - Love Grows (Final Fantasy Viii).flac
\Music\Nobuo Uematsu\Final Fantasy S Generation\09 Unknown - Fragments of Memories [Arranged Version].mp3
\Music\Nobuo Uematsu\Final Fantasy, VIII- Fithos Lusec Wecos Vinosec - The Orchestral Soundtrack\12 Faye Wong; Koji Haij - Ending Theme.flac
\Music\Nobuo Uematsu\Final Fantasy VII- Piano Collections\02 Seiji Honda - Final Fantasy VII Main Theme.flac
\Music\Nobuo Uematsu\Distant Worlds II- More Music From Final Fantasy\10 Nobuo Uematsu - Main Theme of Final Fantasy VII (FINAL FANTASY VII).flac
\Music\Nobuo Uematsu\Final Fantasy VII Advent Children Original Soundtrack\01 Nobuo Uematsu - Opening.flac
\Music\Nobuo Uematsu\Final Fantasy VII Advent Children Original Soundtrack\02 Nobuo Uematsu - The Promised Land.flac
\Music\Nobuo Uematsu\Final Fantasy VII Advent Children Original Soundtrack\04 Nobuo Uematsu - Sign.flac
\Music\Nobuo Uematsu\Distant Worlds- Music From Final Fantasy\03 Nobuo Uematsu - Aerith's Theme (Final Fantasy Vii).flac
\Music\Nobuo Uematsu\Final Fantasy VII Advent Children Original Soundtrack\05 Nobuo Uematsu - Tifa's Theme (Piano Version).flac
\Music\Nobuo Uematsu\Final Fantasy VII Advent Children Original Soundtrack\01 Taizo Takemoto, Toky - Divinity I.flac
\Music\Nobuo Uematsu\Distant Worlds- Music From Final Fantasy\13 Nobuo Uematsu - One-Winged Angel (Final Fantasy Vii).flac
\Music\Nobuo Uematsu\Final Fantasy VII Advent Children Original Soundtrack\10 Koji Haijima - Cloud Smiles.flac
\Music\Nobuo Uematsu\Final Fantasy VII Advent Children Original Soundtrack\11 Taizo Takemoto - End Credits.flac
\Music\Nobuo Uematsu\Final Fantasy X Piano Collections\01 Aki Kuroda - To Zanarkand.flac
\Music\Nobuo Uematsu\Final Fantasy X Original Soundtrack\01 Nobuo Uematsu - Yuna's Theme.mp3
\Music\RIKKI\Suteki da ne\04 RIKKI - Suteki da ne (Instrumental).flac
\Music\Nobuo Uematsu\Final Fantasy X Original Soundtrack\19 Nobuo Uematsu - Ending Theme.mp3
\Music\Nobuo Uematsu\Final Fantasy X Original Soundtrack\21 Nobuo Uematsu - Suteki Da Ne [Orchestra Version].mp3
\Music\Aki Kuroda\Final Fantasy XIII- Piano Collections\10 Aki Kuroda - Prelude to Final Fantasy XIII Full Version.flac
\Music\Masashi Hamauzu\Final Fantasy XIII Original Soundtrack\01 Masashi Hamauzu - Prelude to Final Fantasy XIII.flac
\Music\Aki Kuroda\Final Fantasy XIII- Piano Collections\02 Aki Kuroda - Final Fantasy XIII - The Promise ~ The Sunleth Waterscape.flac
\Music\Nobuo Uematsu\Distant Worlds- Music from FINAL FANTASY Returning Home\08 Masashi Hamauzu - FINAL FANTASY XIII- Fabula Nova Crystallis.flac
\Music\Masashi Hamauzu\Final Fantasy XIII Original Soundtrack\13 Masashi Hamauzu - Ragnarok.flac
\Music\Masashi Hamauzu\Final Fantasy XIII Original Soundtrack\10 Masashi Hamauzu - Lightning's Theme.flac
\Music\Nobuo Uematsu\Distant Worlds- Music from FINAL FANTASY Returning Home\05 Masashi Hamauzu - FINAL FANTASY XIII- Blinded By Light.flac
\Music\Masashi Hamauzu\Final Fantasy XIII Original Soundtrack\15 Masashi Hamauzu - Promised Eternity.flac
\Music\Nobuo Uematsu\Distant Worlds- Music from FINAL FANTASY Returning Home\09 Masashi Hamauzu - FINAL FANTASY XIII- Saber's Edge.flac
\Music\Masashi Hamauzu\Final Fantasy XIII Original Soundtrack\05 Masashi Hamauzu - Atonement.flac
\Music\Masashi Hamauzu\Final Fantasy XIII Original Soundtrack\06 Masashi Hamauzu - Memories of Happier Days.flac
\Music\Masashi Hamauzu\Final Fantasy XIII Original Soundtrack\20 Masashi Hamauzu - Determination.flac
\Music\Masashi Hamauzu\Final Fantasy XIII Original Soundtrack\16 Masashi Hamauzu - Fabula Nova Crystalis.flac
\Music\Masashi Hamauzu\Final Fantasy XIII Original Soundtrack\17 Masashi Hamauzu - FINAL FANTASY XIII - Miracles.flac
\Music\Masashi Hamauzu\Final Fantasy XIII Original Soundtrack\22 Masashi Hamauzu - Ending Credits.flac
\Music\Leona Lewis\Echo\08 Leona Lewis - My Hands.mp3
\Music is not a correct path in Android/Linux (and actually an odd one under Windows), so it's not really surprising. It would require some custom detection of \Music and turning it into /mnt/sdcard/Music, but it's not very logical considering the completely different file systems and way of handling paths in Linux versus Windows.
There is an option in MediaMonkey to use "Linux folder separator (/ instead of \". That may resolve this. If that were the case, wouldn't none of the songs work in any of the music playing applications on the phone? The problem I'm having seems to only be affecting USB Audio Player Pro and not Neutron or PowerAMP players.