# WSL2 Audio Configuration for Microphone Access

This guide explains how to configure Windows microphone access from WSL2 for the MyTTSClient project.

## 🎯 Objective

Enable a Python application in WSL2 to access the Windows microphone for audio recording and transmission to a Wyoming server.

## 📋 Prerequisites

- **Windows 10 (Build 19041+)** or **Windows 11**
- **WSL2** installed and configured
- **Linux Distribution** (Ubuntu 20.04+ recommended)
- **Microphone** connected and working in Windows

## 🔧 Step-by-step Configuration

### 1. Windows Permissions

#### 1.1 Enable Microphone Access
1. Open **Windows Settings** (`Win + I`)
2. Navigate to **Privacy & security** → **Microphone**
3. Enable **"Let apps access your microphone"**
4. Enable **"Let desktop apps access your microphone"**

### 2. WSL2 Configuration

#### 2.1 Update WSL2
```bash
# In PowerShell (Administrator)
wsl --update
wsl --shutdown
# Restart WSL2
```

#### 2.2 Install Audio Dependencies in WSL2
```bash
# In your WSL2 terminal
sudo apt update
sudo apt install pulseaudio pulseaudio-utils
```

#### 2.3 Verify PulseAudio Connection
```bash
# Check connection to Windows server
pulseaudio --check -v
```

**Expected Results:**
- ✅ `N: [pulseaudio] main.c: User-configured server at unix:/mnt/wslg/PulseServer, refusing to start/autospawn.`
- ❌ `E: [pulseaudio] core-util.c: Failed to create secure directory` (see Troubleshooting section)

#### 2.4 Environment Variables (if needed)
```bash
# Add to ~/.bashrc if issues persist
export PULSE_SERVER=unix:/mnt/wslg/PulseServer
export PULSE_RUNTIME_PATH="/mnt/wslg/runtime-dir/pulse"

# Reload
source ~/.bashrc
```

### 3. Test Audio Devices

#### 3.1 List Audio Sources (microphones)
```bash
pactl list sources short
```

**Example Output:**
```
1    RDPSink.monitor    module-rdp-sink.c     s16le 2ch 44100Hz    SUSPENDED
2    RDPSource          module-rdp-source.c   s16le 1ch 44100Hz    SUSPENDED
```

#### 3.2 Test with Python
```bash
# Install Python dependencies
pip install sounddevice numpy

# Test devices
python -c "import sounddevice; print(sounddevice.query_devices())"
```

**Example Output:**
```
  0 pulse, ALSA (32 in, 32 out)
* 1 default, ALSA (32 in, 32 out)
```

## 🔍 Diagnostics and Troubleshooting

### Issue: "Permission denied" on /mnt/wslg/runtime-dir/pulse

**Solution:**
```bash
sudo mkdir -p /mnt/wslg/runtime-dir/pulse
sudo chown $USER:$USER /mnt/wslg/runtime-dir/pulse
chmod 700 /mnt/wslg/runtime-dir/pulse
```

### Issue: "Error querying device -1"

**Cause:** PulseAudio cannot find audio devices

**Solutions:**
1. Check Windows permissions (step 1.1)
2. Restart WSL2: `wsl --shutdown` then relaunch
3. Verify environment variables (step 2.4)

### Issue: No input devices detected

**Solutions:**
1. Test microphone directly in Windows
2. Ensure microphone is not used by another application
3. Restart Windows and WSL2

### Issue: "RDPSource" instead of real microphone

**Explanation:** WSL2 uses RDP (Remote Desktop Protocol) to tunnel audio. `RDPSource` **IS** your Windows microphone.

## 🧪 Validation Tests

### Test 1: PulseAudio Connection
```bash
pulseaudio --check -v
# Should display: "User-configured server at unix:/mnt/wslg/PulseServer"
```

### Test 2: Available Devices
```bash
pactl list sources short
# Should list at least RDPSource
```

### Test 3: Python Recording
```bash
python main.py
# Should display device list and allow recording
```

## 📚 Additional Resources

- [Official WSL Audio Documentation](https://docs.microsoft.com/en-us/windows/wsl/)
- [PulseAudio Documentation](https://www.freedesktop.org/wiki/Software/PulseAudio/)
- [WSL Audio Issues on GitHub](https://github.com/microsoft/WSL/issues?q=audio)

## ⚠️ Known Limitations

1. **Audio Latency**: WSL2 may introduce additional latency
2. **Audio Quality**: RDP compression may affect quality
3. **Permissions**: Windows Updates may reset permissions
4. **Multi-user**: Per-Windows-user configuration

## 🔄 Updates

This guide is based on WSL2 version 2.0+ and Windows 11. For earlier versions, additional steps may be required.

---

**Version:** 1.0  
**Last Updated:** 2025-08-31  
**Tested On:** Windows 11, WSL2 Ubuntu 22.04
```