Wacom Intuos Art Medium crashes Ubuntu when using pen

I followed this excellent tutorial on how to get Wacom graphics tablet working. After the installation, the tablet seems to work well, until I started using the pen. That's when Ubuntu freezes.

The tutorial used to work before, but when I switched to Arch Linux, this happened. I went back to Ubuntu and it happened again.

I am using Wacom Intuos Art Medium (CTH690) on Ubuntu 14.04 LTS

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