diff --git a/module_usb_audio/audio_io/audio_io.xc b/module_usb_audio/audio_io/audio_io.xc
index 368c6ebf..15406aed 100755
--- a/module_usb_audio/audio_io/audio_io.xc
+++ b/module_usb_audio/audio_io/audio_io.xc
@@ -819,7 +819,7 @@ unsigned static deliver(chanend c_out, chanend ?c_spd_out,
 #endif // CODEC_MASTER
 
                     samplesIn[buffIndex][((frameCount-1)&(I2S_CHANS_PER_FRAME-1))+i] = bitrev(sample); // channels 1, 3, 5.. on each line.
-#if ((I2S_DOWNSAMPLE_FACTOR > 1) && !I2S_DOWNSAMPLE_MONO)
+#if ((I2S_DOWNSAMPLE_FACTOR > 1) && !I2S_DOWNSAMPLE_MONO_IN)
                     if ((I2S_DOWNSAMPLE_FACTOR - 1) == downsamplingCounter)
                     {
                         samplesIn[buffIndex][((frameCount-1)&(I2S_CHANS_PER_FRAME-1))+i] =
@@ -838,7 +838,7 @@ unsigned static deliver(chanend c_out, chanend ?c_spd_out,
                             src_ff3v_ds3_voice_coefs[downsamplingCounter],
                             samplesIn[readBuffNo][((frameCount-1)&(I2S_CHANS_PER_FRAME-1))+i]);
                     }
-#endif // ((I2S_DOWNSAMPLE_FACTOR > 1) && !I2S_DOWNSAMPLE_MONO)
+#endif // ((I2S_DOWNSAMPLE_FACTOR > 1) && !I2S_DOWNSAMPLE_MONO_IN)
 
                 }
 #endif
diff --git a/module_usb_audio/devicedefines.h b/module_usb_audio/devicedefines.h
index 61bbbb51..0b133f75 100644
--- a/module_usb_audio/devicedefines.h
+++ b/module_usb_audio/devicedefines.h
@@ -135,12 +135,12 @@
 #endif
 
 /**
- * @brief Only downsample one channel per I2S frame.
+ * @brief Only downsample one channel per input I2S frame.
  *
- * Default: 0 i.e. mono mode is disabled, all channels will be downsampled.
+ * Default: 0 i.e. mono mode is disabled, all input channels will be downsampled.
  */
-#ifndef I2S_DOWNSAMPLE_MONO
-#define I2S_DOWNSAMPLE_MONO (0)
+#ifndef I2S_DOWNSAMPLE_MONO_IN
+#define I2S_DOWNSAMPLE_MONO_IN (0)
 #endif
 
 /**
@@ -148,7 +148,7 @@
  *
  * Default: The number of I2S incoming channels, or half this if mono downsampling is enabled.
  */
-#if (I2S_DOWNSAMPLE_MONO == 1)
+#if (I2S_DOWNSAMPLE_MONO_IN == 1)
     #define I2S_DOWNSAMPLE_CHANS (I2S_CHANS_ADC / 2)
     #if ((I2S_DOWNSAMPLE_FACTOR > 1) && (I2S_MODE_TDM == 1))
         #error Mono I2S downsampling is not avaliable in TDM mode