I just tried with my Dell 2707wfp monitor using an HDMI -> DVI adapter and discovered the problem also happens on there (displays a signal out of range message instead of just going blank though). This narrowed the problem down to the receiver or the graphics driver. I then tried with a laptop with GMA950 graphics using a second DVI -> HDMI adapter and discovered it doesn't happen on Intel graphics. This would indicate a problem with the graphics driver, which is good I guess as it's a fixable problem (many people were previously having issues with Yamaha audio on ATI cards apparently).
If you have ATI graphics, (particularly a 4850 and/or in two of these in Crossfire, though any ATI graphics user could help me potentially), and a rx-v563 receiver could you please try the following steps for me:
1. In Vista, click start (well, the windows icon), right click "Computer" and select "Manage".
2. Press ok to the UAC prompt (unless you turned it off).
3. Open the "event viewer" module, then "custom views", then "administrative events".
4. Select the top event and then hold the down arrow key on your keyboard so it scrolls down the list. If this problem occurs on your graphics card the display should blank, flicker in an odd way or display an out of range error. If this happens, you may be able to restore an image by pressing alt-f4 to close the event viewer window. Otherwise you might have to restart. Make sure you're not doing anything important before you attempt this.
I will try submitting a bug report to ATI, but it'd be nice to know if i'm the only one with this issue before I do.