修复进入通话重新回到录音，录音不了的问题

local_plugins/azure_speech/ios/azure_speech/Sources/azure_speech/AzureAsrHelper.swift

@@ -677,10 +677,18 @@ public class AzureAsrHelper: NSObject {
             audioStream?.recordfile = RecordFile()
         }
     
-        
+        self.audioSourceType = .microphone
         // 修复：移除多余的 audioDataCallback 参数
+         // 修复：添加类型转换
         audioStream?.startAudioRecord(
-            audioSourceType: audioSourceType == .microphone ? .microphone : .external,
+            audioSourceType: {
+                switch audioSourceType {
+                case .microphone:
+                    return SimpleAudioReceiver.AudioSourceType.microphone
+                case .external:
+                    return SimpleAudioReceiver.AudioSourceType.external
+                }
+            }(),
             audioDataCallback: audioDataCallback
         )