Switch your default audio output with a single key — and actually move every running app to the new device — then get a fast, slick AMD-style overlay telling you where the sound went. Built to be bound to a Stream Deck (or any hotkey), but works fine from the command line too.

Windows can change the default output, but it leaves apps that are already playing stuck on the old device. This tool fixes that: it flips the default and re-routes each running app in one go.

• One key per device (e.g. key 1 -> monitor, key 2 -> headset).
• Moves already-running apps to the new device (the part Windows skips).
• Animated overlay: dark panel slides in -> a thin red bar "writes" the label -> short hold -> red bars sweep across and the whole thing wipes away. Fast and unobtrusive.
• Pick the corner (top-right by default) and it adapts to any resolution / DPI (tested target: 3440x1440 ultrawide).
• Zero-config installer: setup.cmd downloads the dependency and lets you pick your devices from a list.
• No admin rights required.

• Windows 10 or 11.
• Windows PowerShell (built in — nothing to install).
• svcl.exe (NirSoft SoundVolumeCommandLine) — downloaded automatically by the installer. It is not bundled in this repo (it has its own freeware license).

1. Download this folder (or git clone it) somewhere permanent, e.g. C:\Tools\audio-switch\.
2. Double-click setup.cmd. It will:
   • download svcl.exe if needed,
   • list your output devices,
   • let you assign two of them to keys 1 and 2 (label + icon),
   • choose the overlay corner,
   • write the config and generate the Stream Deck launchers.
3. In Stream Deck, add two buttons with the action System -> Open, pointing at the two generated .vbs files (the installer prints their names).

That's it. Tap a key — the sound switches and the overlay appears.

powershell -ExecutionPolicy Bypass -File .\audio-switch.ps1 1      # key 1
powershell -ExecutionPolicy Bypass -File .\audio-switch.ps1 2      # key 2
powershell -ExecutionPolicy Bypass -File .\audio-switch.ps1 list   # show devices + active apps

The .vbs launchers run the same thing with no console window flashing, which is what you want for a Stream Deck button.

Settings live in audio-switch.config.json (created by the installer; see audio-switch.config.example.json for the shape). If the file is missing, the script falls back to built-in defaults.

Device matching tries id -> fragment -> name, so even if a device id changes after a reconnection, the name still resolves it.

Colours, speeds, and the hold duration are in the <Storyboard> inside the Show-Toast function in audio-switch.ps1. The reds are #FF564D (light), #ED1C24 (AMD red), #A10E13 (dark); the panel is the #202024->#141418 gradient. The ~1.25 s hold is the gap between the end of the "write" (~0.52 s) and the start of the exit bars (~1.77 s).

The actual switch is just a couple of svcl calls and is effectively instant. The device default is set first (one call), then running apps are moved, and only after that does the overlay (WPF) load — so audio never waits on the animation. Apps already on the target are skipped.

If a key press still feels slightly delayed, the cost is almost always PowerShell process startup, not this script. The launchers already use -NoProfile to minimise it. For truly instant switching you'd avoid spawning a process per press — e.g. keep a resident listener or trigger the switch from an always-running AutoHotkey script. The log (audio-switch.log) records elapsed milliseconds at each stage and a final SWITCH DONE in ...ms, so you can see exactly where the time goes.

svcl /SetDefault changes the default output, but Windows does not move streams that are already open — that's why apps stayed on the old device. The script enumerates every active audio stream (one /scomma call), sets the default, then calls svcl /SetAppDefault per process id for each app not already on the target. Everything moves together, then the overlay is drawn.

• Nothing happens — open audio-switch.log (next to the script): it logs the resolved device, how many apps moved, timings, and any error.
• "svcl.exe is missing" — run setup.cmd, or drop svcl.exe next to the script.
• "no output device matched" — re-run setup.cmd and reselect the device.
• A stubborn app won't follow — some apps (games in exclusive mode, or apps that open the audio stream only once) only re-route on their next sound. Switch before starting the sound, or toggle the audio in that app.
• Overlay on the wrong monitor — it appears on the primary monitor's chosen corner.

• Uses NirSoft SoundVolumeCommandLine (svcl.exe) by Nir Sofer — freeware, fetched at setup time, not redistributed here.
• This project is released under the MIT License.