diff --git a/src/AudioFilterFIR_F32.cpp b/src/AudioFilterFIR_F32.cpp
index f252f4d1..518cb32f 100644
--- a/src/AudioFilterFIR_F32.cpp
+++ b/src/AudioFilterFIR_F32.cpp
@@ -72,7 +72,7 @@ void AudioFilterFIR_F32::update(void)
 }
 
 int AudioFilterFIR_F32::processAudioBlock(audio_block_f32_t *block, audio_block_f32_t *block_new) {
-	if ((is_enabled == NULL) || (block==NULL) || (block_new==NULL)) return -1;
+	if ((is_enabled == false) || (block==NULL) || (block_new==NULL)) return -1;
 	
 	//check to make sure our FIR instance has the right size
 	if (block->length != configured_block_size) {
@@ -100,4 +100,4 @@ void AudioFilterFIR_F32::printCoeff(int start_ind, int end_ind) {
 		Serial.print(", ");
 	}
 	Serial.println();				
-}
\ No newline at end of file
+}