Comment 12 for bug 1674635

I'll setup a test vm and see if I can reproduce this. In the meantime, can you test the 4.4.0-69 kernel in proposed:

https://launchpad.net/~canonical-kernel-team/+archive/ubuntu/ppa/+build/12134676

Note, you need to install both the linux-image and linux-image-extra .deb packages.