mpg321 hangs at least with some mp3's if they have id3v2 tags. After removing those it plays them nicely.
I haven't noticed this. Could you send me a URL to a file which exhibits this behaviour, and how to reproduce? (I have seen mp3 files which screw up with smpeg, but just now in trying to reproduce it I haven't been able to - not regarding id3v2 tags, anyways).
I downloaded Modificar, but had no trouble playing it. Maybe it was another file which had the problems?
Yes, I checked that mp3, and sent the URL to Sam Latinga, who when he gets some spare time will look at it. But I'm not so convinced that these two problems are the same, since that MP3 doesn't have an id3v2 tag in it. So I'm trying to nail down just what's wrong. By the way, the reason SMPEG doesn't barf on bad data is because it's trying to be lax, because there are so many terrible encodings out there.