In my opinion, the quality of online music sources is not high quality, most of them are 128bit mp3s... very few 320bits... and quite rare lossless formats. I just download it to my NAS and listen to it. 2TB with gold music is more than enough

. I can't listen to music online now because the quality is too low.
drive mad
As for the streaming problem, you can replace the USB wifi for Pi3 and it will immediately improve. Because the wifi that comes with the Pi3 is a bit weak (some doctors are fine - my pi3's wifi is also weak and is using USB wifi).