https://code.google.com/archive/p/flukeformac/
Fluke is a small utility for Mac OS that lets you play FLAC files right within iTunes.
Features
16bit/44.1KHz playback
Multiple file and folder handling (the latter from command line only at the moment)
Track number and count support
Known issues
Mac OS X 10.7 Lion Support: is incomplete at this time. To make Fluke run, go into your Applications, right-click on iTunes, head to Get Info, and check off "Open in 32-bit Mode".
Only 16bit/44.1KHz files play fine. Any other resolution affects the speed of playback which is a known Xiph.org issue.
Embedded artwork is not supported. However if you've got an iTunes Store account, select the songs you added, right-click and hit Get Album Artwork.
iPod, iPhone, iPad, Airport Express, Apple TV and other devices from Apple are NOT supported — Fluke uses a third-party library not available on those devices.
CD burning does not work for the same reason as the above.