Client freezes

So I have been having this problem for a while but kept ignoring it because I knew it would get fixed in some patch. Unfortunately it is getting out of hand. So every time I'm afk on the client for more than 10s (this includes waiting in queue) my client just stops respondimg. I tried to repair the client, waited for 3 patches and even got a new security program(I thought it was the automatic scans that was disrupting the client) but nothing worked. I have a pretty good PC, more than capable of watching twitch while playing league and hearthstone all at the same time. I'm sorry if this is a rant but its getting a little frustrating. P.s. If I am posting in the wrong thread please let me know**.**