FLAC's native container format uses OGG-style metadata: <a href="http://wiki.etree.org/index.php?page=FlacMetadata" rel="nofollow">http://wiki.etree.org/index.php?page=FlacMetadata</a><p>Though I've never seen a FLAC file with <i>any metadata at all</i> in the wild: it's always in the filename and accompanying text files. I would end up massaging the metadata into the standard mp4 fields when I transcoded to ALAC.<p>In practice when I've tried seeking in a FLAC file, I usually get a short pause followed by a loud click, and then the timecode is usually wrong or missing entirely. Maybe none of the files had seekpoint data, or the player/decoder implementations I used didn't support them. ALAC always worked perfectly.