From db6a20047eb3d88739bf3d61fc6d2a43eeb77188 Mon Sep 17 00:00:00 2001
From: Thomas Grill <gr@grrrr.org>
Date: Tue, 30 Dec 2025 21:35:20 +0100
Subject: [PATCH 1/2] Remove unnecessary init

---
 AudioFilterBiquad_F32.h | 1 -
 1 file changed, 1 deletion(-)

diff --git a/AudioFilterBiquad_F32.h b/AudioFilterBiquad_F32.h
index 9e15a02..2fa37ee 100644
--- a/AudioFilterBiquad_F32.h
+++ b/AudioFilterBiquad_F32.h
@@ -57,7 +57,6 @@ class AudioFilterBiquad_F32 : public AudioStream_F32
   public:
     AudioFilterBiquad_F32(void): AudioStream_F32(1,inputQueueArray) {
         setSampleRate_Hz(AUDIO_SAMPLE_RATE_EXACT);
-        sampleRate_Hz = AUDIO_SAMPLE_RATE_EXACT;   //  <<<<<<<<<<<<<<<<<<<<<<  CHECK IF NEEDED??
         doClassInit();
     }
     AudioFilterBiquad_F32(const AudioSettings_F32 &settings):

From 039a778b5a0eb7d0ef0983f4c94d021b72de5afd Mon Sep 17 00:00:00 2001
From: Thomas Grill <gr@grrrr.org>
Date: Tue, 30 Dec 2025 21:42:33 +0100
Subject: [PATCH 2/2] Fixes

---
 AudioFilterBiquad_F32.h | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/AudioFilterBiquad_F32.h b/AudioFilterBiquad_F32.h
index 2fa37ee..605f2c9 100644
--- a/AudioFilterBiquad_F32.h
+++ b/AudioFilterBiquad_F32.h
@@ -70,7 +70,7 @@ class AudioFilterBiquad_F32 : public AudioStream_F32
            coeff32[ii] = 0.0;
            coeff64[ii] = 0.0;
            }
-        for(int ii=0; ii<4; ii++) {
+        for(int ii=0; ii<IIR_MAX_STAGES; ii++) {
            coeff32[5*ii] = 1.0;  // b0 = 1 for pass through
            coeff64[5*ii] = 1.0;
            }
@@ -82,7 +82,7 @@ class AudioFilterBiquad_F32 : public AudioStream_F32
     // or from direct setCoefficients() need to be added to the double array
     // and also to the float
     void setCoefficients(int iStage, double *cf)  {
-        if (iStage > IIR_MAX_STAGES) {
+        if (iStage >= IIR_MAX_STAGES) {
            if (Serial) {
               Serial.print("AudioFilterBiquad_F32: setCoefficients:");
               Serial.println(" *** MaxStages Error");
@@ -95,7 +95,7 @@ class AudioFilterBiquad_F32 : public AudioStream_F32
            coeff64[ii + 5*iStage] = cf[ii];  // The local collection of double coefficients
            coeff32[ii + 5*iStage] = (float)cf[ii];  // and of floats
            }
-       doBiquad = true;
+       begin();
        }
 
     // ARM DSP Math library filter instance.
@@ -106,6 +106,7 @@ class AudioFilterBiquad_F32 : public AudioStream_F32
         // Initialize BiQuad instance (ARM DSP Math Library)
         //https://www.keil.com/pack/doc/CMSIS/DSP/html/group__BiquadCascadeDF1.html
         arm_biquad_cascade_df1_init_f32(&iir_inst, numStagesUsed, &coeff32[0],  &StateF32[0]);
+        doBiquad = true;
         }
 
     void end(void) {