ADAU1466 + ES9038Q2M Pi Hat DAC not working

I am working on a project with raspberry pi streamer

and adau1466 DSP (ADAU1466 Core Board Designed for SIGMADSP Engineers Audio Maker DIYER sz898 | eBay)

and es9038q2m Pi hat DAC(ES9038q2m DAC Board Digital Broadcast I2S 32Bit/384K DSD 128 for Raspberry Pi | eBay)

I managed to get the DSP working via USBi programmer and I wanted to test I2S communication to the DAC using a sine wave generator in sigma studio.
The oscilloscope showed proper output on the I2S outputs of the DSP, but the DACs do not deliver proper output and lock led is not lit.
I wonder if these DACs are supposed to work standalone or if they can only be combined with a Raspberry PI. I used the same I2S pins on the DACs GPIO Port as described for the Raspberry Pi GPIO Port.

But this does not work. I cannot make the communication between DSP and DAC work. Has someone tried a similar setup successfully or has anyone an idea why this setup is not working?

Thanks