Asus Zenfone 3 ZE520KL (ASUS_Z017DB)
ROM Build Number = OPR1.170623.026.WW_Phone-15.0410.1712.31 (Android 8.0, Stock Rom)
My Device has Snapdragon 625 with audio support 24bit/192khz
Using versi 704, Hi-Res Output option is dissapear.
I check root folder and found a change, audio_policy_config_configuration now move to vendor/etc/audio (I'm not advanced user, CMIIW). may be this can help.
audio_policy_configuration.xml
audio_effects.conf