Vivo NEX 3s
Android 10
Specifications to its hi-fi DAC: https://www.akm.com/content/dam/documents/products/audio/audio-dac/ak4377aecb/ak4377aecb-en-datasheet.pdf
Currently hi-res output routes the audio to the Snapdragon DAC / audio codec (Qualcomm Aqstic)
Oh, totally forget this thread existed until now
Vivo Nex 3s, Android 10
Hi-Res output technically works, 16 bit all the way up to 384 khz, but (as I have posted in the other threads) not through the dedicated hi-fi DAC
My Nex 3s uses the AK4377A DAC which is very capable
The DAC work with OpenSL or AudioTrack. However both of those output lock the sample rate at 48k which downsamples my hi-res tracks.
So far I've found 2 ways to engage the DAC without downsampling
1. Get a 3rd party equalizer app and enable MusicFX. (I don't need to have equalizer app running). Even then the DAC will not start on its own, I need to go into AudioTrack output first to engage it and then switch it to Hi-Res output. As soon as I exit Poweramp the DAC unloads and I have to repeat the procedure the next time I launch Poweramp. Also any slight ducking in audio will unload the DAC
2. Use Neutron Player
I am just reporting the behaviors I've observed so far, not sure if any of that actually contributes to anything.
Vivo X21A
Android 9
Hi-Res output used to be compatible with the built-in DAC as recent as build 871
Vivo Nex 3s
Android 10
Hi-Res output sample format only 16 bits available where X21A can do 24 bits, not compatible with DAC
Yes I am aware. Noozxoide is never opened or running. I'm just saying that simply having a 3rd party equalizer app is enough to get the DAC to work with hi-res output.
Messed around a bit more and found an interesting behavior.
Back when first installing Poweramp on my new phone I noticed the option to turn on MusicFX was greyed out, now thinking back I believe it's due to the system audio effects keeping out 3rd party apps. So I ended up downloading Noozxoide EIZO-rewire. The MusicFX option became available which suggest that Noozxoide had served as a stand-in for system audio effects. And somehow by doing this the hi-res output is now able to engage my phone's DAC.
Still not a perfect workaround, however. The resolution is stuck at 16bit and sample rate defaults to 48k everytime Poweramp is launched and I have to manually select higher sample rates.
I'm not familiar with the more technical details but my experience with PA on the Vivo X21 has been:
705--Wired Headset/AUX available for OpenSL ES HD but music will not play if I enable it
709--Wired Headset/AUX is not listed for OpenSL ES HD
790--Wired Headset/AUX available for OpenSL ES HD and music plays when it's enabled
If this helps, the phone has a Hi-Fi DAC, in the settings I have Hi-Fi mode enabled for PA. When music is playing through aux in PA 790 the Hi-Fi notification shows up indicating it's active.