I have had my nexus 5 for 7 months without a single issue. I'm running a Sabermod Slimkatbuild and have been for a month with Uber kernel and just today had a issue with screen stuttering. I have had no issues to date. I was flying when this all started so phone was in airplane mode I was listening to music with Play Music from my menova usb otg and typing in quick office. My keyboard and navigation bar started stuttering in and out. I stopped all apps and rebooted and it continues in landscape and portrait on every screen from the boot animation to the app drawer. The only screen it doesn't appear on is the google initial splash screen. I have wiped cache and dalvik and restored a nandroid. Issue persists. The best way i can describe the issue is it appears that my screen size keeps changing and navigation bar rises up from the bottom of the screen overlapping the first one it also effects the widgets keyboard and pattern unlock. I am in the process of downloading the factory images to wipe the device and start fresh but am still trying to figure out what caused this.