Thank you. Pressing all the buttons several times worked. The H9 Max has turned on twice. What could have been the cause? Do these buttons need maintenance? Should I fabricate a boot of some sort? The unit has not been subject to anything other than a normal environment.
Now that the emergency is over, what is the simplest method to make both of my H9 devices identical (presets occupying the same address)? Should I simply create a complete backup with one unit, and then use this backup to restore the second?