I found the same when I was using gReader in China, although audio/video often still wouldn't get through.
Using the internet in China made me pretty paranoid sometimes. Some days you could access a number of sites, then the next day most of those sites would be blocked. Maybe the government gives you a little line to explore ways around the system, then blocks those avenues? Going to baidu.com often worked as a reset button, but at times it seemed that anything that wasn't in Chinese was restricted.