Yosemite Won't Shutdown With External Monitor Connected

Hi there...

I have a MBP 2010 and I've updated Yosemite from Mavericks. Now I'm running the latest 10.10.2.

Ever since I updated to Yosemite, I have had this problem of my computer won't shutdown when an External monitor is connected. This happens only when I put my computer to sleep.However, if I restart the computer and after logged in to the user and tried to shutdown, it shutdown without any problem. Every time I shutdown it just hangs and I had to force shutdown by press and hold the power button. Which I'm sure is not a proper way.

Right now only my external monitor connected to my MBP. So I did unplugged the ext. monitor and tried shutdown and it works fine. But it think this is the temporary solution that I've found but it is annoying to unplug everytime I wanted to shutdown and plug it back in once the computer is up and running. Which is not idle solution at all.

Am I the only one or a lot of people facing this issue? If there is a solution please share. Very much appreciated. Thanks.