In the manual of the H9000 is clearly explained that Eventide products work with a 50 ohm termination but I wonder if it is possible to set the impedance to 75 ohm, since 75 ohm is pretty much the standard of other digital units. I am using an Apogee Big Ben to clock the H9000 but the termination of 50 ohm is considered by the Big Ben "over terminated" and this can cause some problems. Also, I tried to activate the internal termination in the clock page of the settings in the H9000, instead of using a phisical termination on a t-connector attached to the end of the cable and at the input of the H9000, but it seems to do nothing… I wonder if the internal termination is not implemented yet and if at the moment there is only the switch in the GUI which, again, is not working…

There must be an error in the manual, because I'm pretty sure (and confirmed this with a colleague) that the H9000 termination should be 75 ohm.  This is also the value of the internal termination.

The software switch to turn on the internal termination should work.  When you change the switch, do you hear the relay click?