It's not unusual to import audio into Audacity only to discover one or more tracks are too quiet. If you've recorded an interview, for example, one half of the conversation might be louder than the ...
Audacity 4.0 brings a fundamentally new Qt-based interface, a new clip model, and the .aup4 format. Some functions are still missing.
Go to the Recording section. Tick the Sound Activated Recording checkbox. Set the Sound Activation level (in decibel - DB) ...