I know there are posts out there and I've read some, but just doesn't seem like my issue is the same. First off, when I first built the HTPC, I don't think I was getting this issue.
What I get is when I power on the TV, HTPC, and receiver via a Harmony 890 lately when it goes into MC the TV resolution displays 1024x768. If I minimize MC and then maximize, it will go back to 1920x1080. This is happening probably 90% of the time now. Doesn't seem to make a difference if the HTPC is sleeping or awake. So not sure if this is same issues others have, just different outcome, but frustrating, especially as the kids and wife don't want to deal with it and usually just leave until I come in and see they aren't utilizing the entire screen real estate.
Obviously some update has changed a setting somewhere. I haven't checked recently, but did have CEC off because the Harmony didn't like it on. TV is Vizio xvt3d554sv and Receiver is Pioneer VSX-31. HTPC has an i3 processor.