Signal-Android Calls Don't Use Microphone (silent)

[x] I have searched open and closed issues for duplicates
[x] I am submitting a bug report for existing functionality that does not work as intended
[x] I have read https://github.com/signalapp/Signal-Android/wiki/Submitting-useful-bug-reports
[x] This isn't a feature request or a discussion topic

Bug description

When calling someone or answering a call (voice only call, not necessarily video), Signal doesn't use my microphone. I can hear the people on the other end, but they can't hear me. If I change to a bluetooth microphone or switch to speakerphone, they can hear me. However, the speakerphone gives them a lot of feedback, and we usually have to hang up and talk over cellular if I don't have my bluetooth headphones with me.

Important notes:

I am using CalyxOS on a Pixel 3. I know someone else who is also using CalyxOS on a Pixel 3 and has the same issue.
Voice memos work fine.
The green microphone icon in the system tray bar at the top of my phone screen shows up, meaning the microphone is being accessed.
This started happening a few months ago. I think sometime in 2024.

Steps to reproduce

Go to a chat with a friend and hit the phone icon to start a call
When they pick-up, start talking. They won't be able to hear you. or
Have someone call you on Signal
Answer the call and start talking. They won't be able to hear you.

Actual result: My voice isn't picked up and transmitted to the other person on the call. Expected result: My voice would be able to be heard by the other person on the call.

Device info

Device: Google Pixel 3 Android version: 14 CalyxOS version: 5.7.0 Signal version: 7.6.2 (But this started happening a few months ago. I think sometime in 2024.)

Link to debug log

Debug Log

May 24 '24 20:05 lukeganzevoort

Same issue for me, on the latest version of LineageOS for the Pixel 3 both with Signal release version 7.6.2 and beta version 7.8.1

For regular calls and Signal voice messages the microphone works, for Signal calls it doesn't.

May 25 '24 07:05 ghost

I am also experiencing this bug since updating from LineageOS 20 (Android 13) to LineageOS 21 (Android 14) on a Motorola G7 Play. I can also confirm that Signal is able to access my microphone successfully for recording voice messages and other applications are able to successfully record from the microphone. Downgrading to LineageOS 20 works around the bug.

FWIW I am using microG for GCM push notifications, but I doubt that's relevant to this bug.

Jul 09 '24 22:07 Be-ing

This seems likely to be a LineageOS bug rather than a Signal bug, but I'm not certain there isn't a bug in Signal. Multiple devices with multiple applications have been reported as being affected when updating from LineageOS 20 to LineageOS 21: https://gitlab.com/LineageOS/issues/android/-/issues/7007

Jul 18 '24 03:07 Be-ing

I am suffered too (LOS21). Sometime it is working, but mostly not. Sometimes it seems to work to enable permission for micro on a "ask before" base. But that's not reliable too.

Today: Outgoing call: Mic was silent. Incoming call: My counterpart could hear me.

Jul 31 '24 10:07 starbrights

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

Oct 05 '24 10:10 stale[bot]

sadly, this has been coming and going for me, too (LOS 18.1 on vayu; i.e. a rather old LOS).

a couple of updates ago it got much worse. the other side rarely hears me, i'm mostly silent on their side. and when i connect my bluetooth headset, then Signal uses my phone's microphone.

prior to this breakage there were issues with volume, too. i was very quiet, unless i connected my bluetooth headset.

Oct 09 '24 10:10 attila-lendvai

prior to this breakage there were issues with volume, too.

That's probably a different bug. This bug is about zero sound coming through at all.

Oct 09 '24 19:10 Be-ing

After further research, I believe the bug I'm seeing is OS related. Something to do with Android 14 port to pixel 3 (from CalyxOS or LineageOS). I have the same issue on Slack, where when I join a huddle from my phone, the microphone works fine until I hold the phone up to my ear (which switches from speaker mode to phone mode) then the microphone stops working.

Oct 10 '24 12:10 lukeganzevoort

The issue was gone for some time, now it is back. I switched to LOS22 some time ago, but that doesn't seem to trigger this issue. To bad, I am not sure what triggered this behavior. I am just wondering, why other apps (WA, phone, Fritzbox, Satellite) using calls are not suffered. What is special with Signal here? Delete and re-install Signal doesn't help.

For me it is not depending on "holding phone to ear" as @lukeganzevoort mentioned. Same no mic with Video-calls or with BT-headset.

My hardware is beyond1lte (Samsung S10).

Feb 06 '25 08:02 starbrights

The issue was gone for some time, now it is back. I switched to LOS22 some time ago, but that doesn't seem to trigger this issue. To bad, I am not sure what triggered this behavior. I am just wondering, why other apps (WA, phone, Fritzbox, Satellite) using calls are not suffered. What is special with Signal here? Delete and re-install Signal doesn't help.

For me it is not depending on "holding phone to ear" as @lukeganzevoort mentioned. Same no mic with Video-calls or with BT-headset.

My hardware is beyond1lte (Samsung S10).

similar situation here.

i'm on LOS 18 since it was new. LOS 18 stopped getting updates years ago.

it's a xiaomi poco x3 pro.

i used to have a problem with the mic years ago, and then it got fixed by a signal update.

currently, for about 3-4 months now, again i can only talk to people when i put them on the speaker. otherwise my signal transmits silence.

Feb 11 '25 23:02 attila-lendvai

Hello @starbrights and @attila-lendvai, can you please provide logs, preferably after a failed call? We can check.

Feb 14 '25 17:02 jim-signal

@jim-signal : Sorry for late reply. How to do so? Do you mean Signals internal Diagnoese? Which section is of interest? The last lines directly after a call? I have create that and now there is a log.txt. Can I send it just direct to you instead of upload here? Any sensible data in?

Feb 18 '25 06:02 starbrights

@starbrights The instructions for gathering and sending logs is described here. We would look at the time before and during a call, and the device information in the first section of the log. Logs mainly help us rule out issues, so it is hard to predict what exactly we'll see there. You could send the file or link to [email protected] and reference this issue if you can't share here.

Feb 19 '25 21:02 jim-signal

Send the log, hope you can figure out something.

Feb 20 '25 15:02 starbrights

@starbrights Yes, I was able to see your log file, thanks.

I can see that the microphone isn't working for you since no audio data is being sent out. I tested a call on my S10 (exynos) and it worked, but I am on aosp, not lineageos. My logs show that my device is using input "deviceId: 11" whilst your logs show "deviceId: 10", that is the only discrepancy that I see. We don't set these, they are the default from the operating system. The only thing I can try is to set this device to use a different audio interface, which is now active. Please let me know if anything changes for you.

Feb 21 '25 17:02 jim-signal

Thanks for evaluating this. Interesting - we have same device. Maybe a phone today has more than one mic. How you can set this different interface? Let me know how I can test this - do I need new signal version? Is this a problem hardware layer (maintainer of device) or the LOS itself? You know, one blames the other - either user, app, os or device specific layer. Do you compile your AOSP yourself or what is your source.

Feb 21 '25 18:02 starbrights