I recently tried to reset my Smart Hub 2 to factory settings using the reset button on the outside case.
The reset button didn't work - I tried three times in succession, using my usual method, switch-on and hit the rest button with a paper-clip.
The unit would only reset if I used the software command on the hub web-page.
As I have never had this problem before, I'm wondering whether the Firmware changes included disabling of the reset button ?
Press a pin into the recess button for about 20 seconds or until the lights flash.
I've generally found that BT HH5 & Smart Hub need a little time to "wake up" from power on before they'll respond to the reset button. Never had a SH2 though.