I would like to request to add a feature to support all LAME 3.99 or later libs, since it seems Audacity only supports your linked LAME lib version from Buanzo. I’ve tried using latest LAME lib (3.99.5) and I get the following error:
Which is kinda weird since there is not a great change in the command line options from Audacity’s supported LAME version (3.99.3-buanzo) and latest LAME versión (3.99.5 right now).
I suppose Audacity checks the lib code in Windows, since it doesn’t even let me export an mp3, despite being the same command line options in both 3.99.3 and 3.99.5
See this topic for why Audacity requires a lame_enc.dll that supports an extensive feature set. The best recommendation is to use the lame_enc.dll hosted on the buanzo site. You might be able to find a latest libmp3lame.dll online that Audacity will accept, but there is no guarantee.
If you want to use arbitrary LAME versions in Audacity, that is already supported if you install an appropriate LAME.exe (not lame_enc.dll) to C:Program FilesLame for Audacity (or C:Program Files (x86)Lame for Audacity on 64-bit Windows). You can find latest LAME.exe online, for example, in the Rarewares bundles . Then export at the Audacity command-line interface, choosing (external program) when you export. For help, see http://manual.audacityteam.org/help/manual/man/exporting_to_an_external_program.html .
Longer term, I hope we will build a (non command-line) MP3 export options interface that uses LAME.exe directly rather than a .dll. This will probably give more compatibility with arbitrary versions of LAME. So I’ll add your vote, but it isn’t going to happen through the current .dll loading that the Audacity Libraries Preferences uses.