Video too dark when played in secondary monitor (Nvidia card)

I have a multiple monitor setup. Since I installed the codec pack, I got troubles playing video on my secondary monitor, it just goes too dark (in botch windowed or fs modes). If I move the window to the other monitor, colors return to normal, but as I put the window in the other monitor it all turns dark again (mostly blues an green colors, no red at all).

Any idea?

Ps.- I updated the video card driver to the lastest version, nothing changed.

The setup goes like:
Display 1 - HDMI to VGA primary monitor
Display 2 - VGA monitor

Which player did you use before you installed the codec pack?
Which graphics card do you have?
Which version of Windows?
Are the colors of the desktop background and other applications correct on the second monitor, meaning it only occurs with video? Does it happen for both fullscreen and windowed video playback?
I assume you haven't made any recent changes to the display settings in the graphics card control panel?

You should try reconnecting the cable. The symptom you describe can happen if the connection is a bit loose. Also try swapping the two VGA cables and the two monitors. Then we can rule out any issues with the cables and monitors.

Hi.
Used VLC. Windows 7 ultimate x64. Everything wokrs fine, monitor is calibrated (photoshop, browsers, background, games, etc), I use it as main monitor, the only issue is the video playback.
Video card - Asus Geforce 650 ti 1GB, driver Nvidia GeForce Game Ready 347.09 (12/23/2014)

Try a different video renderer:
MPC-HC Options > Playback > Output