So, within the past few weeks I have been experiencing these weird gradient distortions around windows. It seems to be consistent with windows that stay at rest for a long time.
Screenshot...
If I were to close this window and open it again there is no gradient distortion.
Thoughts?
Thats unique 
What are you running? Using the right driver? In terminal:
inxi -SG
Have you tried a different theme?
And last of my multi question answer Is this marco or compiz?
[ ed@edmate1604: ~ ]$ inxi -SG
System: Host: edmate1604 Kernel: 4.4.0-72-generic x86_64 (64 bit) Desktop: MATE 1.12.1
Distro: Ubuntu 16.04 xenial
Graphics: Card: NVIDIA GM204 [GeForce GTX 970]
Display Server: X.Org 1.18.4 driver: nvidia Resolution: [email protected], [email protected]
GLX Renderer: GeForce GTX 970/PCIe/SSE2 GLX Version: 4.5.0 NVIDIA 375.39
I have not tried a different theme. I've not really changed anything recently except for installing updates.
Marco.
Inxi looks good.
Think I would still try a different theme and maybe run marco w/software compositor for a while.
Anything in xorg or kernel logs that may of changed?
cat /var/log/kern.log
cat /var/log/Xorg.0.log
Have you added any PPAs?
##Edit
You could also try dropping back to the previous kernel.
I’ll change to different theme first for a while to see if that fixes it.
Changing the theme did not help. I will another step.
That is a common bug within compton. You should try to edit .compton.conf in your home directory like this: https://ubuntuforums.org/showthread.php?t=2144468 or consider an alternative installation of compton like here: Better Compton Compositing (better than other choices too)
I believe that worked. I haven’t seen the issue since applying solution #2, installing compton.