How to rip CDs in FLAC format using Banshee?
Solution 1:
In Banshee's Edit->Preferences select the "Source Specific" tab, and then select "Audio CDs" under "Source". Under "Input Format" you should be able to select "Free Lossless Audio Codec (FLAC)".
Note: you will need the libflac8 package installed, but this should be installed by default on Ubuntu as part of the GStreamer "good" plugins (gstreamer0.10-plugins-good ).