Will not shut off

Several times I have had my unit refuse to shut down.  Even pushing the power button on the front of the unit does not work.  The only way I can get it off is to unplug the power supply, wait a few seconds and plug it back in.  Anyone else having this problem and if you were able to fix it, how did you do it?  All suggestions appriciated.

You have to press and hold the power button for five seconds in order for the hub to completely shut down. If you simply just press and release the power button, it will just go into sleep mode.

Nope, won’t work.  I’ve tried short pushes, 3, 5, 10 second, even longer and absolutely nothing happens.  The only way to get it to power down is to pull the plug.  This does not happen all the time, just often enough to be annoying.

Edit.  Found out it is not really on, nor is it really off, it is kinda sorta in limbo.  The light on the front is on as well as the light on the adapter but it is not doing anything. As the old saying goes “the lights are on but nobody’s home”.