diff --git a/src/gui/gui.cpp b/src/gui/gui.cpp
index 962c633e8..5f61529c6 100644
--- a/src/gui/gui.cpp
+++ b/src/gui/gui.cpp
@@ -5263,8 +5263,10 @@ bool FurnaceGUI::loop() {
           if (curFileDialog==GUI_FILE_SAVE_DMF_LEGACY) {
             checkExtension(".dmf");
           }
-          if (curFileDialog==GUI_FILE_SAMPLE_SAVE ||
-              curFileDialog==GUI_FILE_EXPORT_AUDIO_ONE ||
+          if (curFileDialog==GUI_FILE_SAMPLE_SAVE) {
+            checkExtension(".wav");
+          }
+          if (curFileDialog==GUI_FILE_EXPORT_AUDIO_ONE ||
               curFileDialog==GUI_FILE_EXPORT_AUDIO_PER_SYS ||
               curFileDialog==GUI_FILE_EXPORT_AUDIO_PER_CHANNEL) {
             if (audioExportFilterExt!="*") {