VAIO SVT131A11L (aka SVT13125CDS) has had a touchscreen/pointer problem ever since upgrading from Windows 8.1 to 10. On startup or coming out of sleep/hibernation, the touchscreen shows two touch images (whatever that graphic is when you touch the screen with your finger) permanently in the middle of the screen and the pointer flickers in and out, alternating between a frozen pointer appearing in the middle of the screen and the actual pointer as I move it around via the touchpad or BT mouse. Display driver is up to date via device manager and I've looked all around for driver updates on Sony's website but nothing for Windows 10 for display for this model. I've also tried calibrating the touchscreen.
The workaround has always been to switch display modes on startup, Win key + P, from PC Screen to Duplicate then back to PC Screen, the static finger prints and pointer disappear and everything works properly.
Now I'm stuck with Windows update version 1607 in the queue because if I allow that update the Win key + P workaround no longer works and the problem becomes permanent. I've tried it twice and had to roll back each time.
Frustrated, I finally did a clean install of Windows 10, the OS definitely runs a bit better (it's quicker in general) but this problem still persists.
I've seen threads about touchpads and touchscreens not working entirely with Windows 10, but nothing like my problem. Any ideas?
Currently running Win 10 v. 1511, 64 bit.