I've bought the hootoo dongle for my new macbook pro 2016 TB, and I also have problems with it.
When I use it on left side ports, it doesn't work properly, there is a "bad contact" when I touch it, so I have to find a position in which the hub works.
But if I use it with one of the two right side ports, that works properly. Stange no ?
Another problem, with an Anker USB-c to Ethernet adapter. Some times ethernet turn off, I have to disconnect and reconnect the dongle...
It's a dongle with ethernet and 3 usb port (but I just have my keyboard plugged in it), and I wonder if it's not a matter of power supply...