windows 7 - Mouse sensitivity not being applied

I have two PCs, one running Windows XP SP3 and the other running Windows Embedded Standard 2009 (WES). WES is similar to Windows XP, I think.

Using TweakUI > Mouse > Mouse sensitivity, the default for the double-click sensitivity is "50". Testing this on the icon on the right (or in Control Panel > Mouse > Double-click speed), I can see that if I click on the far left of the icon, quickly move the mouse to the far right and click again (ie. a double-click spaced ~30 pixels apart) then a Windows double-click event is generated. Fine...but not what I want.

So I change the "Double-click" value in TweakUI to "2" and retest and now the clicks must be really close together to generate a double-click event. Great.

Problem is that on reboot, the value resets to "50" on the WES PC (but remains "2" on the XP box).

I found the relevant registry settings (which apply to Windows 7 and Windows 8, I think):

[HKEY_CURRENT_USER\Control Panel\Mouse]
"DoubleClickHeight"="4"
"DoubleClickWidth"="4"

and for the "Mouse sensitivity > Drag" setting, this is:

[HKEY_CURRENT_USER\Control Panel\Desktop]
"DragHeight"="12"
"DragWidth"="12"

On the WES box, the "Drag" setting is being faithfully saved, either using TweakUI or the registry...but the "Double-click" setting is resetting to "50", even though the registry continues to read "4"!

Any idea how to permanently set the double-click sensitivity to "2"?

Answer

It would seem either another (mouse) "driver" or third party software is perhaps overriding the Windows settings.

As per comments:

...the touchscreen attached to this industrial PC had put something into HKLM\Software\Microsoft\Windows\CurrentVersion\Run which was stomping on the Windows settings.