Improve audio record switch

Signed-off-by: Leo Ma <begeekmyfriend@gmail.com>

library/src/main/java/net/ossrs/yasea/SrsPublisher.java

@@ -246,6 +246,13 @@ public class SrsPublisher {
     }
 
     public void setSendVideoOnly(boolean flag) {
+        if (mic != null) {
+            if (flag) {
+                mic.startRecording();
+            } else {
+                mic.stop();
+            }
+        }
         sendVideoOnly = flag;
     }