I'll copy whole album (seen above) to the partition on 'MusicPC' an try playing the song #4, named "Sueño Latino", a 'problematic' one, directly from AudioPC.
Understood about the 'MusicPC'.
Copying like you just did is a bit dangerous when it is about rights (this is all "since Vista" stuff).
Can you try it the other way around :
(but this is not waterproof for proving)
Have a normal file name(d album), copy that to the Audio PC and now change an n in an ñ.
If it now plays it tells about a "rights" thing.
If it does not play it doesn't tell so much because you still copied the file from that other source.
PS: Don't give up as I hope you'll understand that thare are more users *with* such characters than without. Only English (/ American) will be without it for the native language, while they still may like e.g. French music.
Read : it *has* to be something on your side and when we found it finally, we'll have a laugh over it.
And a drink of course !