I have noticed this same issue a couple times and like others have mentioned pausing and resuming gets it going again. I do have the occasional signal drop from my router and then it reconnects within a few minutes. Does idle master automatically attempt to check for an internet connection after a set amount of time has past since it was disconnected? Perhaps that is where it is hanging up. Just thought I would mention that in case it is helpful. It very well could be Steam too because even when I have a great connection to the internet I get a lot of slow downs when accessing Steam.