Weird thing (Topping E30 DAC + Marantz receiver)

[Megaken]

You can choose whether you apply Audyssey incl. Dyn. EQ, Offset, Dyn. Vol... etc. for each source/input separately. I guess you're just using different setting for your sources and that's why there is a big difference in sound....

I understand that, and I made sure the settings are the same.

I think I may have figured it out though. Both of my phones have a built-in layer of audio processing - one has dolby atoms, and the other has some DTS:X thing, which just come pre-installed from the factory. What I didn't realize is that USB audio seems to bypass those software mods (it doesn't say that anywhere explicitly), and outputs "pure" unprocessed signal, whereas when audio goes out through bluetooth it gets processed by those technologies.

https://dts.com/discover/dtsx-ultra-featured-in-nubia-red-magic-3/