Shutdown sometimes takes a long time

Shutdown usually takes 8 seconds on my computer.

Sometimes (about 10% of the time) shutdown takes 1minute 50seconds to complete.

This is on 16.10 64bit but I’m pretty sure it happened on 16.04.1 as well. This happens on a fresh install (no updates or new software) as well as on an updated system. This is on Skylake i3 and Ivy Bridge i5 desktops with SSDs. There is no error or crash message before or after it happens.

Yes i can confirm it on Ubuntu MATE 16.10 64 bit. But i only testet 16.10 for some days. After that i went back to 16.04.1. There are no problems with a long shutdown time.

Please check point #4 on the common problems thread.
I’m fairly certain this affects 16.10 too.