Intel 4500MHD HDMI output

Hi,

I just bought a widescreen (1366x768) Samsung laptop (vista home premium) with 4500MHD chipset and HDMI output. The HDMI out of the laptop is connected to my AVR which in turn is connected to a projector (720p).
Initially, everything was working fine. When the projector is on, and I turn the AVR on, I get a picture on both the laptop display and the projector. The screen flickers for a seconds, I'm assuming to adjust the the laptop resolution to 1280x720 to match the HDMI out. When I turn the AVR off, the screen flickers again and the laptop switches back to 1366x768.
Now after installing few tools and programs and removing some of the startup programs, the above automatic switching is no longer working. The screen does not flicker when turning the AVR on/off and the picture displayed on the projector screen does not cover the entire screen. The laptop resolution remains at 1366x768. If I change the laptop resolution to 1280x720, the image on the projector streches to cover the entire screen, but the laptop display does not look as good and it remains at 720 after I turn the AVR off.
I have tried playing with all options in the intel driver but with no success. Any idea what what went wrong?

Thanks,
Max