Actually, phred's first suggestion of MP3val does indeed fix some corrupt MP3 files and has done so for me (the GUI is simple to use). Your problem sounds like VBR header corruption; I don't know if MP3val can specifically fix this, but I do know that Foobar2000 can via its Utilities/Fix VBR Header selection tool. Like phred I have never used MP3diags, but I "hear" it can do so also, although when I took a look at it once it seemed less than obvious how to best use, and included a lot of other tag-related stuff most people would use other tools for. "YMMV"