I used to join lot of matches via Quick Match but for past 4 days all it does is putting me in an empty game all by myself, stating that it's waiting for 3 more players.

What happened to Quick Match function? Did it just get broken or something else?

Note I can still join games via server search function.

Doesn't work for me either. And the servers it puts me in, I end up having **** 300 or higher ping.

I usually get ping of 10 or under.