Lethal Voice Router

Thunderstore team: JavaXia

Source version 0.5.2 · Documentation reviewed 2026-10-25 (Asia/Seoul)

Route Lethal Company game audio and incoming player voice to separate Windows output devices. Use F8 to select both outputs and the microphone used for your outgoing voice. Clear Voice is optional and disabled by default.

Windows 10/11 x64 · Lethal Company Mono build · BepInEx 5

Install

For a published Thunderstore release, install Lethal Voice Router with a mod manager. For a local build, import the entire LethalVoiceRouter-0.5.2-modmanager.zip as a local mod in Gale, r2modman, or Thunderstore Mod Manager. Make sure BepInExPack is installed in the selected profile. LethalConfig is optional. This mod runs on each player's PC; the host does not need it for voice relay.

Quick start

1. Launch the game with the mod enabled and press F8.
2. In Output, choose separate playback devices for game audio and incoming voice.
3. In Microphone Input, choose the microphone for your outgoing voice, or leave Use game setting selected to follow the game's microphone choice.
4. To use Clear Voice, enable it in the Clear Voice tab and restart the game. Its default is off.

Separate output requires two playback devices available in Windows. Clear Voice can also be used without separating outputs. Players without this mod can still hear voice sent by someone using Clear Voice; the extended receive filter and receive FEC controls require the recipient to install this mod and enable Clear Voice.

The voice output may not preserve every spatial effect exactly as the game's built-in output. Linux, Proton, and Steam Deck behavior has not been verified.

F8 changes are saved automatically. The output buffer defaults to 40ms and can be set from 20 to 200ms in 10ms steps. If voice breaks up, raise it one step at a time. This value is an output buffer request, not a measurement of total voice latency. Configuration is saved to BepInEx/config/io.lethalloopback.cfg.

The 2026-10-25 startup-output validation, before localization, covered: Release build, 47 basic tests, 16 package checks, 29 Unity checks, and three loopback LAN configurations with all 1,498 received synthetic voice frames decoded. Four output endpoints passed silent playback at 44.1 and 48kHz plus reconnection checks. Two input devices passed preview capture with nonzero meter responses. Thirty additional game-process checks cover active output sessions, per-role policy restoration, normal shutdown, and recovery after a forced process termination. Actual speech, listening quality, and multiplayer between PCs remain unverified. A local ZIP does not imply that a public release has been published.

Startup now reapplies saved per-app output policies even when their values already match. Five fresh-process checks passed without another device selection: original output twice, a saved explicit device twice, and Windows default once. The active session matched after mod initialization. This does not cover engine audio frames before the mod initializes. The final 29 Unity checks include a successful retry after one initial synthetic Esc-input failure; its cause remains undetermined.

Language and device names

English is the default. If LCKR/LCKRL provides a usable font, the existing Korean settings UI remains available automatically. Actual device names are preserved when supported by the selected font; otherwise the F8 window uses numbered device aliases. Device IDs and microphone selections are not translated or reset.

Updating or migrating

Remove the two old DLLs from a manually installed LethalLoopback or LethalVoiceRouter plugin folder before importing the manager ZIP. Preserve BepInEx/config/io.lethalloopback.cfg. Replace the same mod entry when importing an updated manager ZIP. The ZIP is a local mod package, not a shared profile export.

Push-to-talk, voice detection and in-game mute still use the game's settings. Select your microphone in Microphone Input or return to Use game setting. Each sender must enable Clear Voice to improve their outgoing voice.

Troubleshooting

• If F8 does not open, check that both DLLs are in the profile's BepInEx/plugins/LethalVoiceRouter folder.
• Enable missing playback devices in Windows and choose Refresh devices in F8.
• If voice breaks up, raise Output buffer in 10ms steps from its 40ms default.
• If the microphone meter does not move, check the selected input, Windows microphone permissions and mute state.
• For repeated errors, inspect Lethal Voice Router messages in the profile's BepInEx/LogOutput.log.

Select outputs again after moving a profile to another PC. F8 saves automatically; use Apply in LethalConfig. Maximum voice queue defaults to 100ms and supports 20-500ms in LethalConfig or the configuration file. Disabling fallback preserves recording-track separation by muting affected voice blocks when routing fails.

The historical validation counts above refer to the 0.5.1 startup-output build. Version 0.5.2 includes the English documentation and optional localized UI, validated separately on 0.5.1 before the version bump. The source repository contains the detailed localization validation record.

License

The original mod source uses the MIT License. See LICENSE at the ZIP root for its full text. It grants no rights to Lethal Company or third-party assets.