@sangbro For the purpose of playing music via airplay from an iPad to a DAC you don’t need a streamer. Just get a used airport express with digital optical output into your DAC and then you select this airport express as your speaker.
Sound will be good.
If you get a streamer like Bluesound configure the iPad such that it serves merely as remote control, I.e. signal path is from your Wi-Fi to Bluesound to DAC, iPad is not in the path. This solution is very good. If Wi-Fi is good (eg, Google or Linksys mesh), connecting Bluesound via Wi-Fi is superior to Ethernet, I.m.e.
Even better: Get Roon. I run a roon core on a dedicated MacBook via WiFi to a couple OPPO 205 - I have yet to find better (and I have been looking quite a bit).