diff --git a/config.h b/config.h
index 73fa00d..28d5678 100644
--- a/config.h
+++ b/config.h
@@ -106,7 +106,7 @@
 #endif
 
 // FX-CHAIN ENABLE/DISABLE
-//#define USE_FX 1
+#define USE_FX 1
 
 // CHORUS parameters
 #define MOD_DELAY_SAMPLE_BUFFER int32_t(TIME_MS2SAMPLES(20.0)) // 20.0 ms delay buffer. 
@@ -308,7 +308,7 @@
 #    warning >>> With enabled FX a maximum of 14 voices is possible (due to CPU limitations)
 #    define MAX_NOTES 14
 #    if F_CPU > 180000000
-#        warning >>> Enabled FX with clockrate more than 180MHz is not useful due to RAM limitations.
+#        error >>> Enabled FX with clockrate more than 180MHz is not useful due to RAM limitations.
 #    endif
 # else
 #   if F_CPU == 256000000