I recently received an arylic volume knob board and connected it to the Up2stream mini V3 (newest firmware) - but it doesn’t work. 
I also changed and switched the GPIO 1, 2 and Key pins in the ACP (I don’t know the right settings) - still nothing.
You don’t need to change anything in ACP to make it work. The GPIO1/2 is default configured for rotary encoder. And since you’ve changed, please make sure the GPIO1 and GPIO2 has CKEY A, and CKEY B. The KEY in ACP is also configured as default ADCKEY.
OK… I changed the GPIO pins back to standard.
Volume Up seems to work, but volume down is complete strange… it only switches the source from Wi-Fi to Bluetooth, nothing else. 
The push button - supposed to switch between sources I think - does absolute nothing.
Another question: Is it possible, to use the volume knob for controling the group volume?
The beeping sound is really anoying when you turn the volume,i really don’t understand why they decide to put this option on both remote and volume board…
??? What do you mean? I have no beeping here. Only a still not proper working volume knob board. 
On v3 amplifier when you turn the volume up and down on remote or manual with hand on board you have beeping sound for volume steps , very anoying 
Please! 
Can someone help me?
OMG… I just tried the third cable and it seems to work flawlessy! The first cable I tried, was that from the volume board box und the second from one of my seven U2SmV3.
WTF?! Arylic should ask for a different cable supplier or other cable design. I already had 2 big problems, relying on the Arylic-cables (SPDIF IN and now the volume knob board). 
