Thank you KaiS!

Use a different Mode, Preamp Mode is well suited for analog in/out (manual page 37).
It defaults to the optimum sample rate of 192 kHz.

You can store and use a “Setup” for each configuratopn.
Read manual page 29 (DAC), 30 (Pro) or 29 (2/4 Pro SE).

Loading certain “Setups” can be assigned to a button push on the device or remote.
Read manual page 26 (DAC), 28 (Pro) or 30 (2/4 Pro SE).

Watch out:
The  “Remap key” configuration is part of each individual “Setup” and needs to be set for each individual “Setup”.
This can be used to toggle through 2 or more Setups with one single button.

Works like this:
As the button assignment isn’t global, but part of each “Setup”, you can even have different assignments to the same button in each Setup - a nice feature that we can use for the following:

Choose ONE single button that you usually don’t need.
In Setup 1 assign: “load Setup 2”
In Setup 2 assign: “load Setup 1”
Now this single button toggles between both Setups.

This method can be extended to load even more Setups if needed, like:
In Setup 1 assign: “load Setup 2”
In Setup 2 assign: “load Setup 3”
In Setup 3 assign: “load Setup 4”
In Setup 4 assign: “load Setup 1”
Now the single button circles through Setup 1-4, clever, isn’t it?!

As for loading Setups ADI-2 asks for confirmation, a double-push is needed to execute the load.
Holding the button more than 1s, the button‘s original function is available.
Therefore I typically assign the SETUP button to load Setups – sic!

I am using the unit mostly standalone, and it remembers the last sample rate set by SPDIF input  - which is mostly 44.1 or 48kHz in my use case - however, as I would like to use the "slow" AD filter without attenuation below 20kHz, I need a higher sample rate when using analog in.

Of course I also have a PC connected, however, I do not want to power up the PC and manually switch sample rate every time before listening to a vinyl LP through my analog inputs...

Any suggestions?