Actually I don’t suspect that windows handling is causing the problem because as I mentioned earlier I am getting recording audio dropouts when no windows are being switched. Maybe the problems are linked is my only suspicion at the moment. Everything else on my system is fine from a graphics point of view.
As I know that Cubase 7 has none of the problems at all, could there be a difference in what Cubase 8 requires of a graphics card in comparison to that required by Cubase 7 - that would then cause audio dropouts? If so, then I assume Steinberg would be aware of possible problems in the upgrade.
(The graphics card is an NVIDIA MSI GeForce 7600GS 256MB DDR2)