Hi @Anonymous User
A bit of a long shot, but i would try going into your Hitachi TV menu settings and play around with the HDMI and HDMI - CEC options on the television and make sure that you use the supplied power adapter plug that came with the stick and are on the correct HDMI input source on your TV.
If that doesn't work then if you have another television in the house, try that on the new stick and once it has hopefully been setup and uploaded the latest software then swap the stick over to your new Hitachi TV to see if it works.