After some other players tested, I tried to get Volumio up and running. I was expecting a lot issues, as up till now I did not see succes stories. However, to my surprise, the process was not complex.
And the good news, it works flawless. I use it in combination with the Spotify connect plugin. After two weeks testing, no issues found.
Here is what I did:
Install Volumio, Enable SSH, login
3 sudo apt-get update
4 sudo nano /boot/config.txt (add dtparam=spi=on)
8 sudo apt-get install -y python-dev python3-dev
9 sudo apt-get install -y python-spidev python3-spidev
12 dsptoolkit install-profile https://raw.githubusercontent.com/hifiberry/hifiberry-dsp/master/sample_files/xml/dacdsp-default.xml
13 dsptoolkit store
16 sudo nano filter1.txt
18 dsptoolkit apply-rew-filters filter1.txt ( filter1.txt is my specific filter file)
26 dsptoolkit store
Select in Volumio Generic I2C DAC
reboot and done
I am not sure the Sigma driver is running proper (saw some error messages)