Bug: Redirected/Forwarded Incoming Calls Use Phone Speaker Instead of Dongle/Car Audio (Samsung)

[MaxHuiskes]

Bug: Redirected/Forwarded Incoming Calls Use Phone Speaker Instead of Dongle/Car Audio (Samsung)

Summary

When the Samsung phone is connected to Android Auto via the dongle, an incoming call that is forwarded from a secondary phone number/line (e.g., from a work phone) incorrectly routes the audio to the Samsung phone's built-in speaker, completely bypassing the established Android Auto connection.

Steps to Reproduce

1. Connect the Samsung phone to the vehicle using the Wireless Android Auto Dongle.
2. Ensure call forwarding is active from a secondary phone (Phone B) to the Samsung phone (Phone A).
3. Have a third person (Phone C) call Phone B.
4. The call is forwarded and rings on Phone A (your Samsung phone) while it is running Android Auto.
5. Answer the incoming, forwarded call using the Android Auto head unit interface or the steering wheel controls.
6. Observe the audio output device.

Expected Behavior

The audio for the forwarded incoming phone call should be routed through the Android Auto system (the car's speakers and microphone) via the dongle, just like a direct call.

Observed Behavior

When the forwarded call is answered, the audio output immediately switches from the car speakers to the Samsung phone's internal speaker. The call remains "active" on the Android Auto screen, but there is no audio until the user manually switches the output on the phone.

Environment

Component	Detail
Phone Make & Model	Samsung
Android OS Version	[ Android 15]
Dongle Hardware	[ Raspberry Pi Zero 2 W]

Additional Context

• Standard, direct incoming calls function correctly through the dongle.
• The issue only occurs with calls that are forwarded to the Samsung device. This suggests the audio system is not recognizing the forwarded call as part of the primary Android Auto telephony session.