I'm also experiencing this problem, but only with live content on a specific channel.
On Windows 7, 64-bit, live and recorded content play, but the loading spinner stays on for quite a while and I often have to hit reload multiple times. However, it does eventually load if I'm patient.
On Ubuntu, I can play recorded content, but the spinner just spins forever on this channel when the broadcast is live:
The interesting this is I can play live content on other channels, just not this one. Not sure why I'm having these problems with Ubuntu, but there's no ad blocking software active.