diff --git a/module_usb_audio/devicedefines.h b/module_usb_audio/devicedefines.h
index bffb16e5..97f6b968 100644
--- a/module_usb_audio/devicedefines.h
+++ b/module_usb_audio/devicedefines.h
@@ -1331,6 +1331,7 @@ enum USBEndpointNumber_Out
 #endif
 
 /* Apply sample-rate restrictions to full-speed operation */
+#ifndef MAX_FREQ_FS
 #if (NUM_USB_CHAN_OUT_FS > 0) && (NUM_USB_CHAN_IN_FS > 0)
     #if(MAX_FREQ > 48000)
         #define MAX_FREQ_FS              48000
@@ -1344,9 +1345,12 @@ enum USBEndpointNumber_Out
         #define MAX_FREQ_FS              MAX_FREQ
     #endif
 #endif
+#endif
 
 #define MIN_FREQ_FS              MIN_FREQ
 
+
+
 /* Setup DEFAULT_MCLK_FREQ based on MCLK_ and DEFAULT_FREQ defines */
 #if ((MCLK_441 % DEFAULT_FREQ) == 0)
 #define DEFAULT_MCLK_FREQ MCLK_441