Hi @johngreen ,
Sorry to hear about the issues here, even after the SSD swap suggested on your other thread.
If there is no HDMI output and you’ve verified the power is on, the right TV input is selected, etc, then it is most likely a boot failure on the Nucleus.
Since you have bought the Nucleus in the UK, your dealer would be in the best position to assist with the RMA procedure, they can work with our countrywide Roon distributor to repair/replace the unit.