Good Afternoon, My brother's shaman has had a bug since the last patch in which his avatar cooldown is now an hour. Before the patch it'd be ~3-4 minutes and he could basically keep it up 24/7 on his monk and my warrior. Additionally, he used Cannibalism 4 a few nights ago and it went on a one-hour cooldown, though it hasn't done it since.
You should check that the time on that computer is set correctly. It sounds like maybe it hasn't been adjusted for daylight savings time.