Raspberry PI 4 - Tidal and USB DAC

Raspberry Pi 4 and Volumio with MyVolumio subscription to access a Tidal HiFi account.
I have connected to a Cambridge Audio DacMagic device via USB and have also tested a HifiBerry dac+ pro.
I note that regardless of what source or DAC device I use - Local File, Spotify, or Tida and HifiBerry or DacMagic the sampling frequency is always 44khz. My Tidal settings are set to highest quality possible. I don’t understand why this is the case - the DAC Magic should handle upto 96Khz.

Incidentally - I had to manually change the /etc/mpd.conf file to access the USB device. Is this normal?

Any ideas?

Actually I think the problem is with Tidal, Spotify seems ok.