FLAC audio support for OS X 10.9
Sorry to be the bearer of bad news, but native support of FLAC in Mavericks is near non-existent.

Your best bet would be to just convert your FLAC to ALAC, or Apple Lossless Audio Codec.

You can download the free utility XLD, or X Lossless Decoder, to convert.

Download XLD from its homepage here:  http://tmkk.undo.jp/xld/index_e.html