[BUG] Audio Routing Fails in Safari iOS for Twilio Voice SDK

[myst4]

Audio Routing Fails in Safari iOS for Twilio Voice SDK

Environment

• Platform: iOS Safari
• Framework: Javascript
• Twilio Voice SDK: 2.12.3

Description

When initiating a voice call using Twilio Voice SDK in a Javascriot application on Safari iOS, the audio is consistently routed to the speaker instead of the earpiece, regardless of attempted audio routing configurations.

Steps to Reproduce

1. Create a Javascript application using Twilio Voice SDK
2. Initialize a voice call
3. Observe audio output on an iOS device using Safari

Expected Behavior

Call audio should be routed to the device's earpiece by default or through explicit configuration.

Actual Behavior

Call audio is always played through the device speaker, even when attempting to use audio routing methods like:

• device.audio.setAudioConstraints()
• navigator.mediaDevices.selectAudioOutput()
• Twilio.Device.audio.speaker(false)
• Manual device selection techniques

Detailed Investigation

• Confirmed issue occurs across multiple iOS devices
• Attempted solutions include:
  • Explicit audio constraint settings
  • Device enumeration and selection
  • Checking for browser-specific audio routing methods

Potential Limitations

Suspect this may be related to WebRTC audio routing restrictions in Safari iOS.

[charliesantos]

@myst4 thanks for submitting. I'll submit an internal ticket to track this issue.