There is no 100% guarantee, that the cast and Waaagh!TV are synchronous for everyone. Despite this, we try to do our best, so the difference will usually be only a few seconds.
Furthermore you have the possibility to synchronize with the shoutcast by using “speed 0.5-4.5” to speed the game up or to slow it down. If the Cast is ahead in the game, this is unfortunately not a possibility, but this is usually not the case.