Just wanted to pass this info along, I found it on the net (I thought it was here actually) but I can't find it now so I don't know who to give credit to. Anyway...

Cuphead was unplayable for me; the screen would randomly stutter back and forth between normal and completely black and the audio was borked... only one sound could play at a time and the newest sound would cancel out all other sounds and the music as well. Also, the load times were ridiculous.

I'm running Win 7 64 pro.

The fix: find the .exe, right click on it, choose "properties". Then click on the "compatibility" tab and set it to run as XP sp3, disable visual styles, disable screen composition, and run as administrator.

This not only fixed the graphics/audio issues, but now my load times are nearly instantaneous!

I really wish I knew who to give props to for this info, because I'd be Cupheadless right now without it. :P