only seems to work perfectly with CBR

I worked with the LAME developers to fix a few bugs in their VBR support. They also put in an option to reenable VBR headers for nogapped VBR files. Unfortunately, there was a bug in the empeg player software at the time, and I couldn't test it. I haven't gotten a change to test it since. There's not been an official release of LAME since then, though, so you'd have to compile one up from CVS source.