It should be no surprise and highly logical that with the ADI-2 DAC featuring SteadyClock FS we had to update our flagship converter, ADI-2 Pro, to have it as well. This required a modified PCB. Existing units can not be upgraded.
As we had to work on the PCB anyway we also added the AutoDark mode of the DAC, with one 'Pro' difference: the StandBy button stays lit when knobs, buttons and display are off.
I am surprised that Thomann treats this as totally new product, when there are only two smaller (minor) changes. For us it is a slightly updated ADI-2 Pro.
The latest firmware, 174/86, detects the Pro FS and flashes it. Well, indeed the units ship with that firmware.
The FS can be recognized by having 'ADI-2 Pro FS' printed on the front, else everything is absolutely the same.
The manuals are also identical except for the changes with SteadyClock FS and AutoDark:
Official release is on the Frankfurt Musikmesse, so I didn't tell anything