robert_e_bone
I DO think that since this is not a widely-reported issue, that it may well be something local to your particular configuration, and therefor possibly fixable, given enough of a willingness to go through the methodical steps to ferret out why it is occurring.
+1vintagevibe
The video card is a favorite boogie man in the DAW world. When people don't know the cause to the problems it's easy say "video card/driver". I suspect that video cards/drivers are blamed for far more than they are guilty of.
So before you can even point to Sonar you need to confirm:
You have tried THIS driver (the latest)... I bothered to look it up for you so it is as easy as possible:
http://support.amd.com/en-us/download/desktop?os=Windows%208%20-%2064#amd-catalyst-packages AND.. You need to tell us you have done exactly this!!!! :)
You also need to confirm you have windows update
fully up to date, and installed most of the optional updates. I have asked several times maybe I missed it but I didn't get specific feedback.
Check the mouse up on driver is up to date as well and no mouse bloatware installed.
(I think I've been saying this several times now over and over again).
We really don't care who or what is at fault, that seems to be your problem. We want to find the SOLUTION or find some way of confirming this is a bug. A bug can be confirmed not by opinion but by PROOF, and the way to do that is to get somebody else to reproduce the bug.
It is not a blame game, if we thought like that we would never be able to fix anything, we simply want to rule things out before we ever continue.... That is a process. If you choose not to follow it then there is no way we can't help you. And what we write is a total waste of our time as well as yours.
Good luck...