Did this issue just suddenly occur?
Did you change something to, or install something on your system recently that could have an effect?
Do you use v2.8.2 (not a more recent beta)?
Tried with a fresh/clean 'install' (just unzip the zip-package)?
Is your fs resolution setting compatible with your setup (and set to 32 bit, not 16 bit)?
And.. do you have the same issue with similar apps (emu's)?