I tested Fedora 21 beta with their 3.17.1-302.fc21 kernel too and the problem was still there. Initially the bug was reported on Linux Mint 17 XFCE 64-bit with Ubuntu's 3.13.0-24-generic (Ubuntu 3.13.0-24.47-generic 3.13.9) kernel here: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1385165. -- Pozdrawiam / Regards, Orzech