Unable to switch audio devices after start-up and logging in to the Viewer

Environment

Second Life Release 7.1.11.11565212741 (64bit)
Release Notes

CPU: Apple M2 (2400 MHz)
Memory: 24576 MB
OS Version: macOS 13.7.1 Darwin 22.6.0 Darwin Kernel Version 22.6.0: Thu Sep 5 20:43:57 PDT 2024; root:xnu-8796.141.3.708.1~1/RELEASE_ARM64_T8112 x86_64
Graphics Card Vendor: Apple
Graphics Card: Apple M2

OpenGL Version: 4.1 Metal - 83.1

Window size: 2026x1387
Font Size Adjustment: 96pt
UI Scaling: 1.575
Draw distance: 256m
Bandwidth: 3000kbit/s
LOD factor: 2
Render quality: 6
Texture memory: 16384MB
Disk cache: Max size 1638.4 MB (100.0% used)
HiDPI display mode:

J2C Decoder Version: KDU v7.10.4
Audio Driver Version: OpenAL, version 1.1 ALSOFT 1.23.1 / OpenAL Community / OpenAL Soft: OpenAL Soft
Dullahan: 1.14.0.202408091638
CEF: 118.4.1+g3dd6078+chromium-118.0.5993.54
Chromium: 118.0.5993.54
LibVLC Version: 3.0.21
Voice Server Version:

November 13 2024 09:24:31

Description

Switching audio devices after login has never been very reliable but recently, it seemed to work ok.

After this release and/or WebRTC that no longer seems to be the case. If I switch from speakers to Airpods Pro after log in using preferences, the Mac thinks it's switched and non-Viewer audio does appear in the earbuds but the audio (system audio and voice) still output to the speakers. I tried many times.

I know Bluetooth devices can sometimes be problematic so I also tried a pair of speakers with a 3.5mm jack and the same thing happened. The Mac UI told me "External Speakers" were in use but the Viewer did not switch output.

Reproduction steps

• Set your audio output device to the built in speaker.
• Start SL and log in
• Put on Airpods Pro (or probably another audio device)
• Switch to them them using the macOS UI
• Go to the Viewer and using Preferences -> Sound & Media -> Voice Input/Output devices and switch to them also. (They DO appear in the list of devices)
• Note that audio/voice still comes out of the speaker
• Expected the output to come out via the Airpods Pros

Start at Preferences -> Sound & Media, where the Viewer lists the voice input and output devices, and trace how a device change after login reaches audio and voice playback. Reproduce with the built-in speaker and AirPods or external speakers, then verify that both system audio and voice switch to the selected output.