If WAV files are used, a DVD-Video disc is generated, which is not playable. Also, the progress bar is just rolling diagonals during writing, inconsistent messages are shown ("Closing session" most of the time).
If AIFF files are used, Burn asks if and where to convert to WAV. The WAV files generated are only 68 bytes long.
If FLAC files are used, a DVD-Audio disc is correctly generated, which is playable. The progress bar and informational messages are ok.
Version: 2.5.1 (24)
OS: Lion 10.7.4
Player: Pioneer DV-565A