Question Low volume on USB C to AUX

[Quake94]

Hi All

I listen to music in car a lot streaming from Spotify, and have been using a standard AUX connector on a stock radio in a Corolla 2011.
Before the Realme GT2 Pro, I have been using a Lumia 650 and the sound was amazing. Balanced, loud and not lacking in any area. My volume settings were Max on the lumia, and about 40 out of 60 (max) on car radio (and this was already very loud). Before Lumia, I used Galaxy S7 and while the sound quality was slightly worse than Lumia, the loudness was still OK.

I borrowed an OEM Samsung USB C to AUX connector and found out that the sound from GT2 Pro is too quiet. With GT2 Pro volume at Max and my car volume at Max (50) it was much quieter, I could hear noticable distortion, and the sound profile seemed flat. Almost as if there was no pre-amp in the GT2 Pro.

I have a suspicion this is not an isolated issue to Realme, but to all phones that pass audio through USB-C.

My question is:
What would be the best way to get same or better quality of audio as any phone with a pre-amp/integrated audio chip out of Realme?

I am considering:
- Do I need a different USB C to AUX adapter? The adapter tested was original Samsung USB-C to 3.5mm, not a knock-off.
- An aux-to-bluetooth kit, however bluetooth streaming is generally LoFI
- A USB powered DAC? Ideally one that can take bitstreaming audio from phone via USB C and pass into AUX lineout
- Replacing stock radio. I really do not wanna go this route as I feel it is redundant, because my cheap a** Lumia sounds superb on it, and Galaxy S7 was good too.
- Some kind of jerry-rigging offline Lumia to handle audio streamed from GT2 Pro. I have no clue how this would work

Any suggestions are most welcome!

 

[apsol]

It's due to a recent law that limits the sound level on phones and accessories.

I bought the apple 3.5mm usb c dongle and tried it on my car and same story it's very quiet, have to crank to the max.

The European version dongle have limited voltage compared to the US version and Android also has a limit on the volume but you can change if the phone is rooted.

 

[Quake94]

It's due to a recent law that limits the sound level on phones and accessories.

I bought the apple 3.5mm usb c dongle and tried it on my car and same story it's very quiet, have to crank to the max.

The European version dongle have limited voltage compared to the US version and Android also has a limit on the volume but you can change if the phone is rooted.

Hmm.. I read that apple usb-c adapters don't play nice with android phones and are quiet by default.

I've tested a Samsung OEM adapter. As a band-aid solution, I am hotspoting wifi from Realme to Lumia.

EDIT: Here are the findings so far:

1. Tried installing Viper4Android with no avail. Driver not found loop. Maybe someone can figure out a method that works.
2. Confirmed the sound is much louder when Samsung adapter is used with a Galaxy S10+ as compared to Realme
3. Dolby Atmos EQ in Realme actually worsens the quality
4. The volume can be boosted with a shell command, but only with root and after the adapter is plugged, since it acts as external audio device. Tasker or other app can be set to run the command on headphone adapter plugged in

The command is:
su -c "tinymix -D 1 2 100"

Where the "100" is the gain

To display all adjustable variables:

su -c "tinymix -D 1 2 -a"

The default value for Samsung adapter is 83, where 84 is equal to 0dB gain. Maximum range setting is 108, which would be equivalent to +24dB gain.