Where is call audio routing on Android?

Call audio routing refers to how incoming and outgoing call audio is directed on an Android device. There are different audio paths that call audio can take depending on your phone’s capabilities and settings.

By default, call audio is routed through the earpiece on the front of your Android phone. However, you can change this audio path to route the call through external speakers, wired headsets, Bluetooth headsets, and more. Being able to control your call audio routing allows you to optimize the audio experience based on your situation.

Some key audio paths available for routing calls on Android devices include:

• Earpiece speaker
• Main external speaker
• Wired headset
• Bluetooth headset
• Car audio system (when connected over Bluetooth)

In this guide, we’ll provide an overview of call audio routing on Android, explaining how to direct audio through these different paths.

Default Call Audio Route

The default path for call audio on Android routes through the built-in earpiece. When you make or receive a phone call, the audio plays through the phone’s receiver by default unless other audio devices are connected.

This routing behavior is controlled by the Android system and happens automatically. The earpiece speaker is designed specifically for phone calls, making it the optimal default audio path for clarity during calls.

According to Android Stack Exchange, “The earpiece is never used for media in Android, and it can only be used if the phone is in ‘call’ or ‘communication’ (VoIP) state.” [1] So the built-in earpiece is reserved solely for phone call audio.

Some Android phones have a second front-facing speaker that can be enabled during calls for a louder speakerphone effect. But the primary default path utilizes the main earpiece for standard call audio.

Routing Audio to Speakerphone

The speakerphone on Android devices allows you to have calls on speaker without needing to hold the phone up to your ear. This can be useful when you want to have a call with multiple people in the room or just want your hands free during a call.

By default, when you make or receive a phone call on Android, the audio is routed through the earpiece. To route the call audio to the speakerphone instead, simply press the speakerphone button during the call. This button is usually located on the call screen and has an icon like a megaphone or speaker.

Once speakerphone is enabled, the call audio will come out of your phone’s main speaker instead of the earpiece. To switch back to the earpiece, just press the speakerphone button again to disable it.

Some Android devices also have options to automatically route calls to speakerphone. For example, on Samsung Galaxy phones, you can enable the Auto Speaker feature in Call settings. This will automatically route all calls to speakerphone when you answer them [1].

Overall, enabling speakerphone during calls on Android simply requires pressing the designated speakerphone button during a call. Auto speaker options can also be enabled in device settings for convenience.

Routing Audio to Wired Headset

When you plug a wired headset into your Android phone’s headphone jack or USB-C port, the audio automatically routes through the wired headset instead of the phone’s speakers. This is the default behavior in Android.

Here’s how the audio routing works when using a wired headset:

• The wired headset has its own DAC (digital-to-analog converter) and amplifier, which converts the digital audio signal from the phone into an analog signal that can be played through the headset speakers.
• When you plug in the wired headset, it establishes a physical connection with the phone’s headphone jack or USB-C port.
• Android detects this connection and automatically switches the audio output path to route through the wired headset instead of the phone speakers.
• Any audio played on the phone – music, videos, phone calls, notifications, etc. will now be heard through the wired headset.

So in summary, using a wired headset provides a dedicated audio path that keeps the audio private compared to the phone’s speakers. Android handles the routing seamlessly without the need to change any settings.

Routing Audio to Bluetooth Headset

To route audio to a Bluetooth headset on Android:

1. Enable Bluetooth on your Android device through the Settings app.
2. Put your Bluetooth headset in pairing mode so your phone can discover it. Refer to your headset instructions for how to do this.
3. Open the Bluetooth settings on your Android device and select your headset when it appears in the list of Available Devices. Your phone will pair with the headset.
4. Once paired, audio from calls and media will automatically be routed to your Bluetooth headset when it is powered on and in range of your phone. You may get a prompt on first use asking if you want to set it as your preferred audio device.
5. To manually set your Bluetooth headset as the preferred audio device, go to Settings > Connected Devices > Connection Preferences > Bluetooth Audio. Select your headset.

When properly paired and connected, your Android phone will route all call audio to your Bluetooth headset by default whenever you make or receive calls. Bluetooth provides a wireless audio path so you can have hands-free conversations.

For optimal audio quality on calls, use a headset designed specifically for calling versus general wireless listening. Look for headsets marketed for call quality with noise-canceling microphones.

Popular Bluetooth headset manufacturers like Jabra, Plantronics, and JBL make models optimized for call audio. You can also find good budget Bluetooth call headsets from Anker, Mpow, and other brands on Amazon.

Third-party Apps for Audio Routing

Android allows third-party apps to modify the default audio routing behavior for more control. Some popular examples include:

Viper4Android (https://play.google.com/store/apps/details?id=com.vipercn.viper4android_v2): This app has an “audio mode” option to choose between speaker, headset, and bluetooth routing.

Lesser AudioSwitch (https://play.google.com/store/apps/details?id=com.nordskog.LesserAudioSwitch&hl=en_GB): It allows forcing audio output to headphones, speakers, Bluetooth or USB devices. It can also switch microphone sources.

Routy (https://routyaudio.com/): This advanced audio router works across all apps and allows granular audio routing control.

Using such apps provides more options for controlling audio routing between different outputs like speaker, wired headset, Bluetooth etc. Some even allow routing audio between different apps.

Routing Video Call Audio

Video calling apps like Google Duo, Skype, Zoom, and others have specific requirements for routing audio during video calls on Android devices. This is because video calls require synchronizing audio and video streams, which can be complex compared to regular voice calls.

By default, most video calling apps will route audio through the speakerphone during video calls. This allows users to both see and hear the other caller without requiring a headset. However, the audio can be re-routed to wired headsets, Bluetooth headsets, or other audio devices in some cases.

For example, in Google Duo, tapping the speaker icon during a video call will allow switching the audio to a Bluetooth headset that’s paired to your device. Skype similarly has an audio routing selector that allows choosing speakerphone, wired headset, or Bluetooth.

The main challenge with routing video call audio is that switching audio devices can sometimes cause sync issues between the audio and video tracks. So most apps try to detect audio device changes and automatically handle routing to provide the best sync. But glitches can still occur occasionally when changing headsets.

In summary, while audio routing works similarly for video and voice calls, video chat apps have extra complexity to synchronize audio and video that can impact how flexible the audio device switching is. Checking the app’s settings is the best way to understand its audio routing options.

Audio Routing for Accessibility

Android includes specialized audio features to help people with hearing impairments use their devices. This allows routing of audio to hearing aids or other assistive listening devices.

Android has a Hearing Aid mode that allows acoustic coupling with hearing aids set to “M” or telecoil mode. When enabled in Settings, the microphone is used as a telecoil to send audio directly to hearing aids.[1]

Another option is to route audio to Bluetooth hearing aids. Android allows pairing hearing aids via Bluetooth to send call audio, media, and other audio directly to bluetooth hearing aids.[2]

These specialized routing options allow people requiring hearing assistance to directly get audio through their hearing aids, improving accessibility and device usability.

Troubleshooting Audio Issues

Occasionally issues can arise with audio routing on Android devices. Here are some common problems and potential solutions:

If the person you are talking to can’t hear you during calls, first try adjusting the volume using the volume buttons on your device. Also check that the microphone is not blocked or obstructed. Go to your phone’s settings and make sure the microphone is not muted.

If you can’t hear the other person on calls, first turn up the call volume on your phone. Check that your phone is not on speakerphone when you don’t want it to be. Try using wired headphones or Bluetooth headphones to see if the audio comes through properly on those.

Check the accessibility settings and make sure “Mute all sounds” is disabled. Make sure your ringtone and notification volumes are turned up.

You may also want to check for any software updates for your phone, as the manufacturer may have released a fix for audio issues. As a last resort, you can try rebooting your Android device to see if that fixes any software glitches.

Conclusion

In conclusion, understanding how call audio routing works on Android devices is important for optimizing your calling experience. The key points are:

• By default, call audio plays through the earpiece on Android phones. You can change this in Settings.
• To route audio to the speakerphone, simply turn on speaker mode during a call.
• For wired headsets, audio is automatically routed when you plug them in.
• Bluetooth headsets need to be paired before routing audio to them.
• Some third party calling apps allow custom audio routing.
• Video calls route audio based on Settings and Bluetooth pairings.
• Accessibility services can override audio paths to aid hearing impaired users.
• If you have audio issues, check Settings, connections and volume levels.

By understanding the options for call audio routing on your Android device, you can choose the optimal path for your situation. This allows you to hear and be heard clearly on calls, contributing to a seamless calling experience.