Default Dead Wi-Fi connection after sleep

I'm on university wi-fi. I think it's 802.1x, requiring username/domain and password. Which kinda sucks cause Chromecast doesn't work. But anyway, just about every time I turn the screen on, the wi-fi appears connected, but YouTube and facebook just give loading spinners and I think eventually time out. I have to switch the wi-fi off and on again to get the wi-fi to actually work properly. I don't have the same problem with my laptop, so I'm thinking it's a problem with my Note 3. I'm using rooted NB4 if that makes a difference. Any ideas?