Here is what I have on my disk:

Subfolder1: 18 files @192 kbit --> Plays 100% ok
Subfolder2: 11 files @192 kbit --> None of them plays, player skips all files
Subfolder3: 11 files @227 kbit --> Plays 100% ok
Subfolder4: 11 files @192 kbit --> Plays 100% ok
Subfolder5: 13 files @320 kbit --> Plays 100% ok
Subfolder6: 12 files @223 kbit --> None of them plays, player skips all files
Subfolder7: 33 files @192 kbit --> Plays 100% ok