It can conflict with other apps in the system, but generally it should work fine with any number of monitors.

There is a feature to disable for all fullscreen apps. Double-check in f.lux menu > Disable to see that it's off.

Issue solved. Not sure about the reason but I upgraded from Windows 10 1709 to Windows 10 1809.

Just came here to suggest this as well. f.lux just updated for what seems like the third time this week, and either it always happens to update at night or I just notice when it does, because the screen will suddenly become very bright. It's been 11 months since this thread was started and this still hasn't been implemented, even though it seems it should be a fairly easy thing to do. I understand time has to be allocated and prioritized, but this seems like a fairly big ROI improvement in terms of user satisfaction vs time needed to do it. Anyways, I hope you'll consider making it more of a priority.

Set 1200K for day, night, and bedtime. You'll need to enable the wider slider range for this.

Because I haven't heard from anyone else about this yet (we have lots of NVIDIA users!), I would also make sure the audio drivers are current - perhaps it could be on that side too. Can you see if there's a newer sound driver available?

Our 4.101 beta is doing even more aggressive caching of the leaky call, should show slightly lower numbers.

Hello there, thanks for your reply, herf.

Indeed, the "Dynamic Contrast" option was active and, after it, the problem was gone.

I'm not sure if this occurs only with v4 because I don't remember if this monitor option was active before. I use f.lux since 2014 and I have this monitor since January 2015, and this never occurred until now.

Maybe, because of the nature of this option (as you pointed out), together with the dynamic nature of f.lux, which is reacting to the luminosity of the program active, both progressively interfere in each other: one adjust, then the other too, recursively.

Maybe some analisys over the periodicity with f.lux is changing luminosity, to prevent this cycle from occurring, i don't know, it's only a suggestion.

@herf Moving sliders "physically works", meaning I can grab the temperature slider and move it back and forth, but there is no effect on the screen at all.

I updated to the latest driver, 425.31, for now it seems Flux is working through a sleep (I didn't even restart between the driver update, and the following sleep). Will keep you posted!

Ah, fixed it. For some reason I had Guadalajara's clock. Thank you.