Android Auto – Frequently Poor Audio Quality

Mfg

Hello everyone,

For the past few weeks I’ve been using Android Auto with a new vehicle. My Google Pixel 6a runs GrapheneOS (2025090300) and is fully up‑to‑date. Thanks to the team for keeping GrapheneOS current — I really appreciate the effort!

I’m on Android Auto version 14.7.652684‑release.

Issue:
When Android Auto is connected, the audio quality in apps such as Tidal 2.162.0, AntennaPod 3.9.0, and several others is often noticeably degraded. It appears that the input gain for the Android Auto source is set too low — or incorrectly — causing spoken or sung vocals to sound distorted. Interestingly, the navigation voice from Magic Earth does not exhibit this problem.

Questions:

Is this issue known?
Could it stem from Android Auto on GrapheneOS, from the individual apps, or from the car’s head‑unit?
On a regular Android Auto build, there seems to be a way to adjust the input sensitivity. Does GrapheneOS expose a similar setting, and if so, where can it be found?

Any insights or guidance would be greatly appreciated. Thank you!

Mfg

de0u

Mfg For the past few weeks I’ve been using Android Auto with a new vehicle.

Indicating the make, model, and year of the vehicle might be useful.

Mfg

Hello everyone and thank you for your reply de0u

I am using a Porsche Boxster GTS (981) from 2015, equipped with a PCM 3.1 head‑unit that has been retro‑fitted for CarPlay and Android Auto.

Device setup:

Phone: Google Pixel 6a running GrapheneOS (2025100901) – fully up‑to‑date.
Android Auto version: 15.3.653814‑release.

Current behavior

With CarPlay and an iPhone the audio works flawlessly; the iPhone allows adjustment of the output volume.
When using Android Auto (via Bluetooth) the output volume cannot be adjusted on the phone or on the PCM.
Changing the codec (e.g., SBC ↔ AAC ↔ LDAC) does not affect the issue. (Everything works fine via the aux cable and the media can be adjusted.)
In several media apps (e.g., Tidal 2.164.2, AntennaPod 3.9.0) the audio quality degrades: the input gain for the Android Auto source appears to be set too low, resulting in distorted vocals.
Navigation prompts from Magic Earth are unaffected, suggesting the problem lies in the music/audio stream rather than the overall Bluetooth link.

What I have tried

Adjusting volume settings on the PCM – not possible for the Android Auto source.
Modifying codec settings on the phone – no change in perceived gain or distortion.
Verifying that the same head‑unit works perfectly with CarPlay or Android via Aux Cable.
I tried adjusting the media autoplay on my phone, but it didn't work. That means the audio level stays the same.

Open questions

Is this a known issue with Android Auto on GrapheneOS, or with the PCM 3.1 firmware?
Could the problem stem from the individual apps, the head‑unit, or the Android Auto implementation itself?
On a stock Android Auto build there is usually a hidden “input sensitivity” option. Does GrapheneOS expose a comparable setting, and if so, where can it be found?

Any insights, work‑arounds, or references to similar cases would be greatly appreciated. Thank you for your help!

Mfg

brightjob4495

I have a similar issue with Qobuz. Audio quality through Android Auto is way worse than when using bluetooth directly. I've always assumed it was an issue with the app or some weird EQ settings in Android Auto that I never managed to change.

chinook

brightjob4495 hmmmm, out of the curiosity, can you try Symfonium please? (app.symfonik.music.player) - I'll try Qobuz on my side, because Symfonium works flawlessly for me and I get a proper quality.

Mfg

brightjob4495
Thank you for sharing your experience, especially regarding Qobuz. It reinforces the impression that the problem is not limited to a single streaming service – both Tidal, AntennaPod, and now Qobuz suffer from the same degradation when played through Android Auto on my Pixel 6a (GrapheneOS).

From what I have observed:

The issue appears only when the audio path goes through Android Auto (Bluetooth A2DP to the PCM 3.1).
Direct Bluetooth playback (without Android Auto) delivers the expected loudness and clarity, even with the same apps.
Navigation prompts (Magic Earth) remain unaffected, which suggests that the Android Auto audio pipeline for media streams is applying an unintended gain reduction or EQ curve.

If anyone has identified a workaround—such as a hidden setting in the Android Auto developer options, a specific codec configuration, or a firmware tweak for the PCM 3.1—I would be very interested in trying it. Likewise, any information on whether this is a known limitation of GrapheneOS’s Bluetooth stack or of the PCM’s Android Auto integration would be valuable.

Thanks again for confirming that the problem is not app‑specific.

Mfg

chinook

Thanks for the suggestion! I’ll give Symfonium (app.symfonik.music.player) a try and report back with the results.

In the meantime, could you let me know:

Which Android Auto version and phone model you’re using?
Whether you had to adjust any codec settings (e.g., force AAC, LDAC, or SBC) before testing Symfonium.
If you use PCM 3.1, was firmware updated to the latest version at the time of your test.

I’ll run the same checks on my Pixel 6a (GrapheneOS 2025090300) with Android Auto 14.7.652684‑release and get back to you shortly.

Appreciate the help!

chinook

Mfg Sure.

latest, I think? 15.3.653814
nope, I just randomly connected my phone (I ha AA installed before) I use for everything, and accidentally I had Symfonium running. Normal, proper, good quality music ensued. I didn't set up anything else, it was first time using AA on there. I normally use SBC because my headphones offer comparable sound quality as with LDAC on 990 kbps. So no, SBC.
yes, it's always latest from the stable channel (currently 2025100901 - you seem to be approx. 10 releases late). It's Pixel 9 Pro XL

Mfg

chinook

Symfonium works perfectly in terms of audio quality.

The problem is not codec‑related – both SBC and LDAC behave the same way.
It is not a firmware bug in the PCM 3.1 – the head‑unit is up‑to‑date, and CarPlay works perfectly, so the hardware path is fine.
The issue is app-specific: Symfonium uses a different audio pipeline inside Android Auto, as do Tidal, Qobuz and Spotify. I tested Spotify too. This suggests that these apps handle the audio stream differently when handing it over to Android Auto, e.g. by applying custom audio effects or changing the loudness.