feat: add microphone selection to settings

Adds a dropdown in Settings to choose which audio input device to
use for voice mode. Enumerates devices via the browser's
mediaDevices API and persists the selection in AppSettings.
The useVoice hook passes the selected deviceId to getUserMedia().

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/src-tauri/src/models/app_settings.rs

@@ -70,6 +70,8 @@ pub struct AppSettings {
     pub dismissed_update_version: Option<String>,
     #[serde(default)]
     pub timezone: Option<String>,
+    #[serde(default)]
+    pub default_microphone: Option<String>,
 }
 
 impl Default for AppSettings {
@@ -87,6 +89,7 @@ impl Default for AppSettings {
             auto_check_updates: true,
             dismissed_update_version: None,
             timezone: None,
+            default_microphone: None,
         }
     }
 }

app/src/components/settings/MicrophoneSettings.tsx

@@ -0,0 +1,101 @@
+import { useState, useEffect, useCallback } from "react";
+import { useSettings } from "../../hooks/useSettings";
+
+interface AudioDevice {
+  deviceId: string;
+  label: string;
+}
+
+export default function MicrophoneSettings() {
+  const { appSettings, saveSettings } = useSettings();
+  const [devices, setDevices] = useState<AudioDevice[]>([]);
+  const [selected, setSelected] = useState(appSettings?.default_microphone ?? "");
+  const [loading, setLoading] = useState(false);
+  const [permissionNeeded, setPermissionNeeded] = useState(false);
+
+  // Sync local state when appSettings change
+  useEffect(() => {
+    setSelected(appSettings?.default_microphone ?? "");
+  }, [appSettings?.default_microphone]);
+
+  const enumerateDevices = useCallback(async () => {
+    setLoading(true);
+    setPermissionNeeded(false);
+    try {
+      // Request mic permission first so device labels are available
+      const stream = await navigator.mediaDevices.getUserMedia({ audio: true });
+      stream.getTracks().forEach((t) => t.stop());
+
+      const allDevices = await navigator.mediaDevices.enumerateDevices();
+      const mics = allDevices
+        .filter((d) => d.kind === "audioinput")
+        .map((d) => ({
+          deviceId: d.deviceId,
+          label: d.label || `Microphone (${d.deviceId.slice(0, 8)}...)`,
+        }));
+      setDevices(mics);
+    } catch {
+      setPermissionNeeded(true);
+    } finally {
+      setLoading(false);
+    }
+  }, []);
+
+  // Enumerate devices on mount
+  useEffect(() => {
+    enumerateDevices();
+  }, [enumerateDevices]);
+
+  const handleChange = async (deviceId: string) => {
+    setSelected(deviceId);
+    if (appSettings) {
+      await saveSettings({ ...appSettings, default_microphone: deviceId || null });
+    }
+  };
+
+  return (
+    <div>
+      <label className="block text-sm font-medium mb-1">Microphone</label>
+      <p className="text-xs text-[var(--text-secondary)] mb-1.5">
+        Audio input device for Claude Code voice mode (/voice)
+      </p>
+      {permissionNeeded ? (
+        <div className="flex items-center gap-2">
+          <span className="text-xs text-[var(--text-secondary)]">
+            Microphone permission required
+          </span>
+          <button
+            onClick={enumerateDevices}
+            className="text-xs px-2 py-0.5 text-[var(--accent)] hover:text-[var(--accent-hover)] hover:bg-[var(--bg-primary)] rounded transition-colors"
+          >
+            Grant Access
+          </button>
+        </div>
+      ) : (
+        <div className="flex items-center gap-2">
+          <select
+            value={selected}
+            onChange={(e) => handleChange(e.target.value)}
+            disabled={loading}
+            className="flex-1 px-2 py-1 text-sm bg-[var(--bg-primary)] border border-[var(--border-color)] rounded focus:outline-none focus:border-[var(--accent)]"
+          >
+            <option value="">System Default</option>
+            {devices.map((d) => (
+              <option key={d.deviceId} value={d.deviceId}>
+                {d.label}
+              </option>
+            ))}
+          </select>
+          <button
+            onClick={enumerateDevices}
+            disabled={loading}
+            title="Refresh microphone list"
+            className="text-xs px-2 py-1 text-[var(--text-secondary)] hover:text-[var(--text-primary)] hover:bg-[var(--bg-primary)] rounded transition-colors disabled:opacity-50"
+          >
+            {loading ? "..." : "Refresh"}
+          </button>
+        </div>
+      )}
+    </div>
+  );
+}

app/src/components/settings/SettingsPanel.tsx

@@ -2,6 +2,7 @@ import { useState, useEffect } from "react";
 import ApiKeyInput from "./ApiKeyInput";
 import DockerSettings from "./DockerSettings";
 import AwsSettings from "./AwsSettings";
+import MicrophoneSettings from "./MicrophoneSettings";
 import { useSettings } from "../../hooks/useSettings";
 import { useUpdates } from "../../hooks/useUpdates";
 import ClaudeInstructionsModal from "../projects/ClaudeInstructionsModal";
@@ -59,6 +60,8 @@ export default function SettingsPanel() {
       <DockerSettings />
       <AwsSettings />
 
+      <MicrophoneSettings />
+
       {/* Container Timezone */}
       <div>
         <label className="block text-sm font-medium mb-1">Container Timezone</label>

app/src/components/terminal/TerminalView.tsx

@@ -6,6 +6,7 @@ import { WebLinksAddon } from "@xterm/addon-web-links";
 import { openUrl } from "@tauri-apps/plugin-opener";
 import "@xterm/xterm/css/xterm.css";
 import { useTerminal } from "../../hooks/useTerminal";
+import { useSettings } from "../../hooks/useSettings";
 import { useVoice } from "../../hooks/useVoice";
 import { UrlDetector } from "../../lib/urlDetector";
 import UrlToast from "./UrlToast";
@@ -23,8 +24,9 @@ export default function TerminalView({ sessionId, active }: Props) {
   const webglRef = useRef<WebglAddon | null>(null);
   const detectorRef = useRef<UrlDetector | null>(null);
   const { sendInput, pasteImage, resize, onOutput, onExit } = useTerminal();
+  const { appSettings } = useSettings();
 
-  const voice = useVoice(sessionId);
+  const voice = useVoice(sessionId, appSettings?.default_microphone);
 
   const [detectedUrl, setDetectedUrl] = useState<string | null>(null);
   const [imagePasteMsg, setImagePasteMsg] = useState<string | null>(null);

app/src/hooks/useVoice.ts

@@ -3,7 +3,7 @@ import * as commands from "../lib/tauri-commands";
 
 type VoiceState = "inactive" | "starting" | "active" | "error";
 
-export function useVoice(sessionId: string) {
+export function useVoice(sessionId: string, deviceId?: string | null) {
   const [state, setState] = useState<VoiceState>("inactive");
   const [error, setError] = useState<string | null>(null);
 
@@ -20,14 +20,19 @@ export function useVoice(sessionId: string) {
       // 1. Start the audio bridge in the container (creates FIFO writer)
       await commands.startAudioBridge(sessionId);
 
-      // 2. Get microphone access
+      // 2. Get microphone access (use specific device if configured)
+      const audioConstraints: MediaTrackConstraints = {
+        channelCount: 1,
+        echoCancellation: true,
+        noiseSuppression: true,
+        autoGainControl: true,
+      };
+      if (deviceId) {
+        audioConstraints.deviceId = { exact: deviceId };
+      }
+
       const stream = await navigator.mediaDevices.getUserMedia({
-        audio: {
-          channelCount: 1,
-          echoCancellation: true,
-          noiseSuppression: true,
-          autoGainControl: true,
-        },
+        audio: audioConstraints,
       });
       streamRef.current = stream;
 
@@ -62,7 +67,7 @@ export function useVoice(sessionId: string) {
       // Clean up on failure
       await commands.stopAudioBridge(sessionId).catch(() => {});
     }
-  }, [sessionId, state]);
+  }, [sessionId, state, deviceId]);
 
   const stop = useCallback(async () => {
     // Tear down audio pipeline

app/src/lib/types.ts

@@ -100,6 +100,7 @@ export interface AppSettings {
   auto_check_updates: boolean;
   dismissed_update_version: string | null;
   timezone: string | null;
+  default_microphone: string | null;
 }
 
 export interface UpdateInfo {