macOS over Airplay - terrible sound quality

Using the latest Deezer app on my mac, streamed via Airplay (2 I think) to a Marantz PM9000N, the sound quality is terrible - I get noise, glitches, etc.. really poor - the Tidal app from the same machine to the same app etc, is perfectly fine, as is Apple Music and Amazon Music - just Deezer. Really really poor. No idea why, or what I can do about it, other than dump Deezer (which I’m sorely temped, but its got a good catalogue).