Audacity has it's own MP3 CODEC, but RB requires you to have one i beleive
Download one and install it.

Personally i like to always export wave files and convert to MP3 afterwards in a 3dr party program like Lame. That way i always have the complete wave file to store.


HP Win 11 12 gig ram, Mac mini with 16 gig of ram, BiaB 2025, Realband, Reaper 7, Harrison Mixbus 9 32c , Melodyne 5 editor, Presonus Audiobox 1818VSL, Presonus control app.