ba3c66f6_MP3val_0_1_8__Documentation__Comments
[WARNING message] Wrong number of MPEG data bytes specified in VBRI header [Fixable?] + [Comments] 
Like with Xing header. VBRI is the other way to store VBR information in the first MPEG frame, but it seems to be used much more rarely.
MP3val 0.1.8: Documentation
Comments