Was hoping someone else could confirm similar issues and hopefully provide (or point me in the direction of a fix).
Running WMC on Windows 7 x64 HTPC in full media center mode outputting to a Vizio TV.
If I start watching a movie and then minimize the screen to something smaller than full screen, the video is properly re-sized along with the WMC movie.
If however, I then maximize back to full screen or drag the windows to a larger size, one of three things happen:
1) Things work normally (but this is very rare)
2) The video image stays the same size as the smaller window and the rest of the window is just black
3) The screen may change size, but the underlying video is scaled improperly, resulting in only part of the image being displayed.
I have done up this little diagram that shows the issue. A,B, and C are basically showing what the yellow circle looks like full screen size, then minimized to the top right corner, then maximized again. D is showing the issue sometimes seen as described in #3 above:
This is happening when viewing movies via the netflix plugin in WMC - I don't believe it is happening (or at least not often) when viewing DVDs, etc.
This machine is running an ATI video card. I have tested this on laptop with a 3 year old NVIDIA card and I don't seem to experience the problem.