HDMI splitter @ LCD TV+Projector: strange problem since Win7/8 update

[escknx]

I have projector and LCD TV connected via passive HDMI splitter to HDMI output of Sony laptop with Radeon 5650. They both worked well at the same time on 1920*1080 until last Win7 updates.
Now I can't use them on 1920*1080 - TV works fine, but projector has horrible distorted colors to green side even if I turn off TV. Once I switch resolution to 1680*1050 everything work(separately or together).
This situation appears on Win8 as well. Using fresh installed Win7 with driver ver 12.10 I have them work properly. But after Win7 makes updates I have a pain switching down resolution if I want to see something on projector.
I can't determine exactly which update makes this.
Does somebody have same problem?
Reinstall Win7 and turn off updates will solve the problem, but these updates should be turned off for forever, that's not a best idea. Moreover I can't use freshly bought Win8 because of that.

[jagabo]

Try forcing the output to RGB or YUV.

[escknx]

Walked through Catalyst CC and can't find this option.
Should I use any other utility?