There’s been lots of changes in the graphics implementation on Windows since 8.0.1. Please try updating to the latest develop branch and let us know if you’re still seeing problems.
I think I found my “homemade” problems: I used spectrogramImage.clear(spectrogramImage.getBounds(), Colours::white);
for clearing the image and spectrImGraphcs to paint in the image. Changing spectrogramImage.clear(spectrogramImage.getBounds(), Colours::white); to spectrImGraphcs.fillAll(Colours::white); seems to have solved both my problems.