Just a reminder, I've posted before. I have the same issue on one windows 7 computer only. I believe the icons change location because this particular monitor is a 27" Asus. It also works through an audio receiver, my speakers are connected to the audio
receiver as well.
I always shut my computer down at night, also I shut off the monitor.
I have to remember to turn on both the monitor and receiver on before I boot up the computer. Icons remain the way I left them, all is well if I do that. Booting up the computer first, then turning on the receiver and monitor, the desktop icons get rearranged.
On booting up the OSr looks for all the hardware attached, in my case if the receiver is not turned on, the computer does not see the monitor or it's size, so I believe the OS rearranges the the icons to some default pattern. I have tested this several times
the rearranged pattern is the same.
I have a second computer and third computer all windows 7, within sight of this one, both have a standard Samsung 22" monitors, each monitor is plugged into the tower's motherboard and or video card. I have tested both by turning the monitor off and re
booting, no change to icon positioning. On these monitors the icons do not under any circumstances rearrange themselves. I believe the difficulty lies in the booting up sequence, the OS must see the monitor early in the boot up.