Do You mean that the module is transparent for couple of seconds ? It's an animation. Please try play with interval value in module settings, use a smaller number than 5000.
I have the same problem! I chanced the interval value in module settings to 4000, 400 ... there is still the same! The module isn't transparent for a couple of seconds - it's transparent all the time. Some modules are completely white.
I'm using the exact same browser and there is no issue like that. Maybe I do not understood it correctly. Do You mean that images are blurry maybe ? If yes than in K2 additional settings in NSP configuration select a different image format to be used instead of Generic.