Just a thought:
I believe mp3 tags have different versions. Is it possible the program you used to fill in the tag information was storing it in a newer version that your Sonatas system could not read?
Also did you change the actual names of the files themselves and not just the ID3 tags?
I believe mp3 tags have different versions. Is it possible the program you used to fill in the tag information was storing it in a newer version that your Sonatas system could not read?
Also did you change the actual names of the files themselves and not just the ID3 tags?