Having the same issue. It is accompanied by the screen going black for 1 or 2 seconds.
Linux 3.16.0-34-generic #47~14.04.1-Ubuntu SMP Fri Apr 10 17:49:16 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1413127 Title: WARNING: CPU: 3 PID: 2121 at /build/buildd/linux-3.16.0/drivers/gpu/drm/i915/intel_uncore.c:47 assert_device_not_suspended.isra.8+0x43/0x50 [i915]() To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1413127/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
