Yep we have this issue too.
As well we also get intermittent access to the internet. Days, weeks, months and all will be fine. Then some days students can log in, but no web pages will load at all. RM have acknowledged there is an issue with RM Buzz on ChromeOS which the developers are working to fix...
As soon we disable the RM Buzz extension it all works perfectly.
Anyone else having the issue I've described?
Thanks