Spdif out on DAC hat on Rpi4

Help needed, my setup:

Rpi4 dac hat with LR rca + spdif out
Setting generic I2S latest version Volumio
Tried every relevant setting like hifberry digiberry etc

Payed spotify plugin works fine with rca analog out (192 kHz)

Now spotify plugin won’t work with spdif
Webstations eg radio do work fine with spdif)

However airplay (spotify YouTube) from my iphone to raspberry works with spdif (44.1kHz)

I think I’m close but could you give me any guidance?

Thanks Martin

Spotify with 192kHz?

Yes, via the oversampling in volumio, I’ve choosen 192kHz because that’s the max my dac hat spdif supports.

ah…ok. I didn’t know this option.

I’m surprised because resampling is done by mpd and mpd is not used by Spotify (both plugins)…

Sorry for my confusion, achim. I must have mixed up things:
When my spotify plug-in in Volumio plays via rca out of my Dac-hat shows 44.1 kHz. When i play webradio it resamples to 192 kHz.
When i connect from the same Dac-hat the spdif to my external Dac (D50S) it shows ‘unlock’ and does not give any sound. If i use AirPlay from my iphone is plays and shows 44.1 kHz.
When i choose webradio in volumio it plays and shows 192 kHz.
Note: the resample rate i have set to 192 kHz because this is the max the spdif of my Dac-hat can do.

Thanks for your comment, you are right. I was mistaken, see my reply to achim above. But still i can’t stand why the Spotify plugin is not working via spdif because it does via rca and webradio and AirPlay.
Any suggestions?