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 ;-)

A Tribe Called Red - The Virus Ft. Saul Williams, Chippewa Travellers

Tierra Whack - Mumbo Jumbo

RL Grime ft. Djemba Djemba - Valhalla

Baja Frequencia - Que Calor

Baja Frequencia - Know Who You Are