Desktop locks up on USB Tethering

[krumm]

Here's a odd one:

I'm running Mint 17.2 with Cinnamon desktop on a Lenovo X1 Carbon. I often need to tether to my iPhone 6 for network connectivity. My preference is to use USB tethering for battery life and security reasons. It's detected as a USB Ethernet device with DHCP and works great.

The problem is that every SECOND time I connect the USB cable to tether, the desktop locks up. Ctl-Alt-BkSpace is the only option at that point. This is really annoying as you can guess.

I've looked through /var/log/* and ~/.cinnamon/glass.log for clues, but can't find anything to go on.

Any ideas where else to look or what else to do? Maybe it's time to try moving to KDE...