[CLIENT] Games fail to start and I get a penalty for it :(

I'm on EUW server. Since the introduction of the new champ select, I keep having problems with starting a game. When all champs are selected and the actual game is supposed to start, a pop-up window tells me that the game "has failed to start", that I should restart the client and try again. It happened to me quite often in the last few days, approximately every 5th game. Now it happened 3 times in a row. And every time it happens again, I get another penalty for "abandoning" a game during champion selection, and I have to wait 30min (at least) to retry. I probably get reduced League Points for allegedly queue-dodging too. It is unfair and annoying. I'm being punished for client bugs :( I don't have connection problems or any other impairment on my computer, and it never happened before the introduction of the new champ select. Please fix this. Am I really the only one with this problem? I found no similar thread here so far... Edit: It only happened when I chose Sona, but then again, I chose Sona 80% of all games, so I didn't find it noteworthy until I read that there is a spectator bug with Sona too. Maybe this helps.