Question about flash player and possible network problem?

Our computers are networked and don't have administration rights. We are trying to watch a stream from an educational source called channel one. (www.channelone.com). We are having problems getting it to work on the non administrator side. I have tried different flash player versions and all seem to fail. It will work on the admin side but when you go to the user side it may play once and then not again or it may not play at all. I have tried using IE and FF as the browser but it makes no difference. I don't know what else to add to help out with diagnostics. The strange thing about it is that most of the computers will work but a select few in a certain area will not. All the computers are exactly the same specs.