Nostalrius Begins - Quality wow vanilla realm (1.12)

They were working earlier today, I logged out, came back a few hours later and now neither channel is working. I can see people talking in them but I cannot talk in them. /4 and /5 both do nothing.

All other channels work correctly.

I have left the channels and rejoined them, logged out completely and back in again and deleted my WDB contents. No luck. Any ideas?