If Youtube videos do not play reload the page, that's a Youtube bug.
Or maybe now, a few years later, it's a new bug ;-)

Colin Stetson - Cryosphere

Colin Stetson - The stars in his head (Dark Lights Remix) (Montreal Oct 2010)

Mr. Scruff - Stockport Carnival

The Kilimanjaro Darkjazz Ensemble - Lead Squid (excerpt)

The Kilimanjaro Darkjazz Ensemble - The Nothing Changes