Is it possible that there is a bug in the MPEG Decoder?
I noticed recently, that Mp3tag usually shows MPEG-1 Layer 3 audio files erroneously as "MPEG 1 Layer I" if the "Emphasis" bits are set to anything other then "None" (i.e. "50/15", "CCITJ.17" or "Unknown"). In this case, playing length, bitrate and stereo mode are usually also shown wrongly.
I could "repair" a set of these files using MP3SE by stating that "Emphasis" was "None" (well, it wasn't, actually... but for test's sake, it's just 2 bits) - all info came suddenly up correctly!
Interestingly enough, most players would decode the MP3 correctly as "MPEG-1 Layer 3", some stating a wrong "Emphasis" (i.e. Winamp 2.78c would swear it was "illegal"). So I assume this might be a bug in the underlying MP3 decoding library - could this be fixed for Mp3tag?