diff --git a/代码/workspace_robo4/robocode.ui/src/main/java/net/sf/robocode/ui/dialog/PreferencesSoundOptionsTab.java b/代码/workspace_robo4/robocode.ui/src/main/java/net/sf/robocode/ui/dialog/PreferencesSoundOptionsTab.java
index d642d20..d41274b 100644
--- a/代码/workspace_robo4/robocode.ui/src/main/java/net/sf/robocode/ui/dialog/PreferencesSoundOptionsTab.java
+++ b/代码/workspace_robo4/robocode.ui/src/main/java/net/sf/robocode/ui/dialog/PreferencesSoundOptionsTab.java
@@ -228,6 +228,7 @@ public class PreferencesSoundOptionsTab extends WizardPanel {
 				if (AudioSystem.getMixer(mi).getSourceLineInfo(clipLineInfo).length > 0) {
 					mixers.add(mi);
                     AudioSystem.getMixer(mi).close();
+                
 				}
 				
 			}
@@ -299,7 +300,7 @@ public class PreferencesSoundOptionsTab extends WizardPanel {
 			Mixer mixer = AudioSystem.getMixer((Mixer.Info) getMixerComboBox().getSelectedItem());
 
 				mixerClassName = mixer.getClass().getSimpleName();
-			
+			mixer.close();
 		}
 		if (mixerClassName != null) {
 			props.setOptionsSoundMixer(mixerClassName);