Make audio sample rate user-configurable

- Add sample rate dropdown in UI with Opus-supported rates (8k/12k/16k/24k/48kHz)
- Add sampleRate parameter to setAudioConfig RPC handler
- Validate sample rate is one of the 5 Opus-compatible values
- Configuration takes effect on next audio restart (Apply button)

jsonrpc.go

@@ -1000,7 +1000,7 @@ func rpcGetAudioConfig() (AudioConfigResponse, error) {
 	}, nil
 }
 
-func rpcSetAudioConfig(bitrate int, complexity int, dtxEnabled bool, fecEnabled bool, bufferPeriods int, packetLossPerc int) error {
+func rpcSetAudioConfig(bitrate int, complexity int, dtxEnabled bool, fecEnabled bool, bufferPeriods int, sampleRate int, packetLossPerc int) error {
 	ensureConfigLoaded()
 
 	if bitrate < 64 || bitrate > 256 {
@@ -1012,6 +1012,10 @@ func rpcSetAudioConfig(bitrate int, complexity int, dtxEnabled bool, fecEnabled
 	if bufferPeriods < 2 || bufferPeriods > 24 {
 		return fmt.Errorf("buffer periods must be between 2 and 24")
 	}
+	validSampleRates := map[int]bool{8000: true, 12000: true, 16000: true, 24000: true, 48000: true}
+	if !validSampleRates[sampleRate] {
+		return fmt.Errorf("sample rate must be one of: 8000, 12000, 16000, 24000, 48000 Hz")
+	}
 	if packetLossPerc < 0 || packetLossPerc > 100 {
 		return fmt.Errorf("packet loss percentage must be between 0 and 100")
 	}
@@ -1021,6 +1025,7 @@ func rpcSetAudioConfig(bitrate int, complexity int, dtxEnabled bool, fecEnabled
 	config.AudioDTXEnabled = dtxEnabled
 	config.AudioFECEnabled = fecEnabled
 	config.AudioBufferPeriods = bufferPeriods
+	config.AudioSampleRate = sampleRate
 	config.AudioPacketLossPerc = packetLossPerc
 
 	return SaveConfig()
@@ -1375,7 +1380,7 @@ var rpcHandlers = map[string]RPCHandler{
 	"setAudioOutputSource":    {Func: rpcSetAudioOutputSource, Params: []string{"source"}},
 	"refreshHdmiConnection":   {Func: rpcRefreshHdmiConnection},
 	"getAudioConfig":          {Func: rpcGetAudioConfig},
-	"setAudioConfig":          {Func: rpcSetAudioConfig, Params: []string{"bitrate", "complexity", "dtxEnabled", "fecEnabled", "bufferPeriods", "packetLossPerc"}},
+	"setAudioConfig":          {Func: rpcSetAudioConfig, Params: []string{"bitrate", "complexity", "dtxEnabled", "fecEnabled", "bufferPeriods", "sampleRate", "packetLossPerc"}},
 	"restartAudioOutput":      {Func: rpcRestartAudioOutput},
 	"getAudioInputAutoEnable": {Func: rpcGetAudioInputAutoEnable},
 	"setAudioInputAutoEnable": {Func: rpcSetAudioInputAutoEnable, Params: []string{"enabled"}},

ui/src/routes/devices.$id.settings.audio.tsx

@@ -144,6 +144,7 @@ export default function SettingsAudioRoute() {
     dtxEnabled: audioDTXEnabled,
     fecEnabled: audioFECEnabled,
     bufferPeriods: audioBufferPeriods,
+    sampleRate: audioSampleRate,
     packetLossPerc: audioPacketLossPerc,
   });
 
@@ -153,12 +154,12 @@ export default function SettingsAudioRoute() {
     send("setAudioConfig", config, (resp: JsonRpcResponse) => {
       if (handleRpcError(resp)) return;
 
-      // Update all state values from the config
       setAudioBitrate(config.bitrate);
       setAudioComplexity(config.complexity);
       setAudioDTXEnabled(config.dtxEnabled);
       setAudioFECEnabled(config.fecEnabled);
       setAudioBufferPeriods(config.bufferPeriods);
+      setAudioSampleRate(config.sampleRate);
       setAudioPacketLossPerc(config.packetLossPerc);
       notifications.success(m.audio_settings_config_updated());
     });
@@ -292,20 +293,18 @@ export default function SettingsAudioRoute() {
           title={m.audio_settings_sample_rate_title()}
           description={m.audio_settings_sample_rate_description()}
         >
-          <div className="text-sm text-gray-700 dark:text-gray-300 font-medium">
-            {(() => {
-              const rateMap: Record<number, string> = {
-                32000: "32 kHz",
-                44100: "44.1 kHz",
-                48000: "48 kHz",
-                96000: "96 kHz"
-              };
-              return rateMap[audioSampleRate] || `${audioSampleRate} Hz`;
-            })()}
-            <span className="text-xs text-gray-500 dark:text-gray-400 ml-2">
-              (auto-detected from source)
-            </span>
-          </div>
+          <SelectMenuBasic
+            size="SM"
+            value={String(audioSampleRate)}
+            options={[
+              { value: "8000", label: "8 kHz" },
+              { value: "12000", label: "12 kHz" },
+              { value: "16000", label: "16 kHz" },
+              { value: "24000", label: "24 kHz" },
+              { value: "48000", label: "48 kHz (default)" },
+            ]}
+            onChange={(e) => handleAudioConfigChange({ sampleRate: parseInt(e.target.value) })}
+          />
         </SettingsItem>
 
         <SettingsItem