A lightweight, keyboard-first desktop audio mixer overlay for windows written in Rust, featuring app-specific volume control and zero-latency global push-to-talk, currently supporting Discord.
Navigate Up/Down
Volume Down/Up
Mute Selected
Open/Close Discord
Oto strips away mouse navigation entirely, allowing you to fine-tune your desktop audio pipeline instantly via a lightweight global keyboard overlay.
Control active process volumes, mute apps, and select settings without reaching for your mouse. Built for developers and Vim power users.
Direct integration with Windows WASAPI audio endpoints ensures lag-free volume routing, per-app mixing, and system-level audio responsiveness.
Uses local Discord IPC socket communication to let you adjust per-user volume inside your voice channels directly, bypassing Discord's restrictive overlay whitelist.
Because Discord restricts local RPC socket access to whitelisted games, you must configure a private developer application. This runs entirely locally on your machine, ensuring 100% decentralized data privacy.
During developer setup, Discord requires a designated redirect URL. Use the local address below:
http://127.0.0.1Local OnlyGo to the Discord Developer Portal and click New Application. Choose a name like "Oto Mixer".
Select OAuth2 from the left menu. Under Redirects, add http://127.0.0.1 and save changes.
Copy your Client ID and Client Secret (reset secret if needed). Open Oto's settings (⚙ Gear Icon), paste them in, and click save. On restart, authorize the popup window to grant local RPC access.
Everything you need to know about setting up and running Oto on your Windows system.
No. Oto runs entirely in standard user-space. It uses native Windows WASAPI COM endpoints to adjust session volumes without needing elevated system administrative rights.
Discord limits local RPC socket integrations. Using private developer credentials bypasses these restrictions, keeping Oto serverless and private.
Yes. For optimal overlay drawing and zero performance impact, we recommend running your games in **Borderless Windowed** mode.
Oto is written in native Rust. It operates in the background using **less than 10MB of RAM** and practically **0% CPU**, ensuring zero impact on your framerates.
Download the Windows installer and start mixing your audio instantly without touching your mouse. 100% free and open-source.