diff --git a/sw_usb_audio/app_usb_aud_phaten_golden_6ch/src/extensions/dnr/dnr_dsp.c b/sw_usb_audio/app_usb_aud_phaten_golden_6ch/src/extensions/dnr/dnr_dsp.c
index d7de4f5..cbfccb0 100644
--- a/sw_usb_audio/app_usb_aud_phaten_golden_6ch/src/extensions/dnr/dnr_dsp.c
+++ b/sw_usb_audio/app_usb_aud_phaten_golden_6ch/src/extensions/dnr/dnr_dsp.c
@@ -16,12 +16,17 @@
 
 #if DNR_ENABLE == 1
 unsigned  g_dsp_eof = 0;
+extern float g_dnr_level; 
 void dnr_exchange_buffer(int32_t *data) {
     static unsigned buff_index = 0;
-    write_to_sample_in_buf(data[1], buff_index, 0);
-    read_from_sample_out_buf(&data[1],buff_index, 0);
+    int dnr_level = (int)g_dnr_level;
+    if (dnr_level != 0) {
+        write_to_sample_in_buf(data[1], buff_index, 0);
+        read_from_sample_out_buf(&data[1],buff_index, 0);
+    }
     data[0] = data[1];
 
+
     buff_index++;
 #if DNR_11MS
     if (buff_index == 128)