Webrtc voices are doubling up

[Sandbox5913]

Environment

Latest firestorm and SL viewer

Description

when testing webrtc on a mainland sim we noticed that everyones voice was doubling up.

Reproduction steps

voice sounds like its echoing / your voice is playing twice to everyone else
perhaps its running in both 'restrict voice to this parcel only' mode and sim wide. on vivox voice doesn't work when in 'restrict voice to this parcel only' mode. So it may be an issue with the parcel itself <Dubia 117,16,66> so that might be worth investigating

---

[kylelinden]

QA to attempt to repro and document repeatable steps.

[maestrolinden]

Hi @Sandbox5913 , I have a few questions for you:

1. It looks like region Dubia was moved to a non-webRTC simulator version (currently Second Life Server 2025-04-24.14648572313), so we don't have that repro case anymore. Are you able to reproduce this issue on demand at any regions currently using webRTC?
2. If you can reproduce the issue, could you please paste your 'about second life' text for full environment info?
3. What are the steps to reproduce this bug? I gave it a try, crossing back and forth between parcels on different voice channels (estate voice channel vs private/parcel channel), but I'm not able to reproduce any 'doubling up' or echo effect on demand. See below for details of what I tried.

In case you're looking for a helpful test region, we have some good ones up on the beta grid, named 'webRTC1' and 'webRTC2'. I tried to reproduce your echo issue at that location, but I'm having trouble reproducing it.

Here's what I tried:

1. Have 2 avatars visit secondlife://Aditi/secondlife/webRTC2/156/164/23

• This region is configured to use webRTC, and includes a few different parcel settings:
  • The big parcel (takes up ~80% of the region area) is using the public/spatial voice channel
  • The parcel marked with a magenta volume is its own voice channel; the 'Restrict voice to this parcel' option is enabled
  • The parcel marked with a yellow volume is also its own voice channel
  • The parcel marked with a block volume has voice disabled; the 'Enabled Voice' option is disabled
  • The adjacent 'webRTC1' region has an identical configuration

2. UserA: start speaking in spatial voice chat

• UserB: verify you hear UserA and that there is no echo effect or "doubling up"

3. UserA: continuing to speak in nearby chat, walk into the parcel marked by the magenta volume (on a private voice channel)

• UserB: verify you stop hearing UserA as soon as they cross into the other parcel

4. UserB: walk into UserA's parcel

• UserB: verify you start hearing UserA as soon as you enter their parcel (without echo effect)

5. UserB: walk into the original parcel

• UserB: verify you stop hearing UserA as soon as you change parcels

6. UserA: walk into the original parcel that UserB is in

• UserB: verify you start hearing UserA as soon as you enter their parcel (without echo effect)

I'm observing the expected behavior when I do this. In case it's a factor, I've pasted my environment below:

Maestro viewer environment

UserA (speaking avatar):

Second Life Release 7.1.15.15596336374 (64bit)
Release Notes

You are at 155.7, 164.0, 22.9 in webRTC2 located at simhost-07c23d76c83837d55.aditi
SLURL: secondlife://Aditi/secondlife/webRTC2/156/164/23
(global coordinates 260252.0, 245412.0, 22.9)
WebRTC-Voice 2025-07-31.16657051566
Release Notes

CPU: Apple M1 Pro (2400 MHz)
Memory: 16384 MB
OS Version: macOS 15.5.0 Darwin 24.5.0 Darwin Kernel Version 24.5.0: Tue Apr 22 19:54:49 PDT 2025; root:xnu-11417.121.6~2/RELEASE_ARM64_T6000 x86_64
Graphics Card Vendor: Apple
Graphics Card: Apple M1 Pro

OpenGL Version: 4.1 Metal - 89.4

Window size: 1109x652
Font Size Adjustment: 96pt
UI Scaling: 0.75
Draw distance: 96m
Bandwidth: 10000kbit/s
LOD factor: 1.125
Render quality: 1
Texture memory: 10922MB
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 1.24.2 / 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: Secondlife WebRTC Gateway 

Packets Lost: 0/948 (0.0%)
August 04 2025 11:37:37

UserB (listening avatar):

Second Life Release 7.1.15.15596336374 (64bit)
Release Notes

You are at 159.8, 169.1, 23.0 in webRTC2 located at simhost-07c23d76c83837d55.aditi
SLURL: secondlife://Aditi/secondlife/webRTC2/160/169/23
(global coordinates 260,256.0, 245,417.0, 23.0)
WebRTC-Voice 2025-07-31.16657051566
Release Notes

CPU: Intel(R) Core(TM) i7-4930K CPU @ 3.40GHz (3402.14 MHz)
Memory: 32704 MB
OS Version: Microsoft Windows 10 64-bit (Build 19045.6159)
Graphics Card Vendor: NVIDIA Corporation
Graphics Card: NVIDIA GeForce GTX 1080/PCIe/SSE2

Windows Graphics Driver Version: 32.0.15.6094
OpenGL Version: 4.6.0 NVIDIA 560.94

Window size: 1918x1773
Font Size Adjustment: 96pt
UI Scaling: 1
Draw distance: 128m
Bandwidth: 10000kbit/s
LOD factor: 1.375
Render quality: 3
Texture memory: 8192MB
Disk cache: Max size 1638.4 MB (33.9% used)

J2C Decoder Version: KDU v7.10.4
Audio Driver Version: OpenAL, version 1.1 ALSOFT 1.24.2 / OpenAL Community / OpenAL Soft: OpenAL Soft
Dullahan: 1.14.0.202408091639
  CEF: 118.4.1+g3dd6078+chromium-118
CEF: 118.4.1+g3dd6078+chromium-118.0.5993.54
  Chromium: 118.0.5993.54
LibVLC Version: 3.0.21
Voice Server Version: Secondlife WebRTC Gateway 

Packets Lost: 0/3,887 (0.0%)
August 04 2025 11:40:18

[maestrolinden]

Looking at the parcel settings around Dubia 117,16,66, I see that:

• this parcel uses the public/estate voice channel
• there's an adjacent parcel in Dubia, which is also on the public/estate voice channel
• there's an adjacent parcel in Webworm, which is also on the public/estate voice channel
  • Webworm appears to have been on Second Life Server 2025-04-24.14648572313 for quite some time (for a few months at least). So it would have been running on vivox.

When this bug was reported, Webworm was on Vivox while Dubia was on webRTC. I believe that this was a factor. I can reproduce voice 'doubling up' now, when I do the following:

1. UserA and UserB: login to a webRTC region (any parcel on the estate/public voice channel should do)
2. UserA: speak in nearby voice chat

• UserB: note that UserA's voice sounds 'normal'

3. UserA: walk across the boundary into the Vivox region
4. UserA: note that UserA's voice becomes inaudible and that their voice dot disappears. This is "expected", because UserA's viewer isn't sending voice data to webRTC.
5. UserA: walk back across the boundary to the webRTC region

• UserB: note that UserA's voice sounds much louder and has a bit of an echo with very short (~20ms) period. It sounds as though UserA's voice stream is being heard twice.

@Sandbox5913 is this ^ what you may have observed when you wrote this report? Could the speaker have been in a neighboring Vivox-mode region before talking in Dubia and sounding 'doubled up'?

[roxanneskelly]

Build can be found here: https://github.com/secondlife/viewer/actions/runs/16785949004

[roxanneskelly]

PR is #4494