diff --git a/pasada-lib/iir_filter.cpp b/pasada-lib/iir_filter.cpp
index 9b19cfd..6dcaf74 100644
--- a/pasada-lib/iir_filter.cpp
+++ b/pasada-lib/iir_filter.cpp
@@ -5,7 +5,9 @@
 #include "iir_filter.h"
 #include <iostream>
 
+#ifndef DEBUG_IIR
 #define DEBUG_IIR 0
+#endif
 
 #if (DEBUG_IIR == 1)
 #define DEBUG_PRINT(expr) do { expr; } while (0)
diff --git a/pasada-lib/ssf_filter.cpp b/pasada-lib/ssf_filter.cpp
index 1ad5cec..7fa724b 100644
--- a/pasada-lib/ssf_filter.cpp
+++ b/pasada-lib/ssf_filter.cpp
@@ -9,6 +9,17 @@
 #include <iomanip>
 #include <iostream>
 
+#ifndef DEBUG_SSF
+#define DEBUG_SSF 0
+#endif
+
+#if (DEBUG_SSF == 1)
+#define DEBUG_PRINT(expr) do { expr; } while (0)
+#else
+#define DEBUG_PRINT(expr) while(0) { expr; }
+#endif
+
+
 static std::vector<double> make_ones(size_t sw) {
     std::vector<double> ones;
     ones.resize(sw);
@@ -66,15 +77,15 @@ double SsfStepDetector::filter(double ssf) {
     if (num_samples == LEN_INIT) {
         // initial threshold setting
         ssf_threshold = 3.0 * ssf_mean * 0.99; // see Zong 2003 for the magic numbers
-        //std::cerr << "before prime()" << std::endl;
+        //DEBUG_PRINT(std::cerr << "before prime()" << std::endl);
         f_ssf_threshold_smoothing.prime(ssf_threshold);
     } else if (num_samples > LEN_TH_WIN) {
-        //std::cerr << "adaptive threshold setting" << std::endl;
+        //DEBUG_PRINT(std::cerr << "adaptive threshold setting" << std::endl);
         // adaptive threshold setting
         // +2 is half the window size
         // TODO: param upon SsfFilter.upslope_width/2 instead of hardcoding -- also f_ssf_threshold_smoothing(), nb. should be even number
         if (num_samples == n_refr + 2) {
-            //std::cerr << "setting adaptive threshold setting" << std::endl;
+            //DEBUG_PRINT(std::cerr << "setting adaptive threshold setting" << std::endl);
             ssf_threshold_nm1 = ssf_threshold;
             // the ssf peak comes 3 samples (half-window + 1 sample) after the crossing
             ssf_threshold = f_ssf_threshold_smoothing.filter(ssf) / ((double) f_ssf_threshold_smoothing.size()) * 0.6;
@@ -138,19 +149,19 @@ void RunningQuality::append(std::vector<double> &rawBeat, std::vector<double> &r
 
     if (beatTemplates.size() == 0) {
         // cannot correlate the first beat, no template yet
-        std::cerr << "(0) first beat -> addTemplate()" << std::endl;
+        DEBUG_PRINT(std::cerr << "(0) first beat -> addTemplate()" << std::endl);
         addTemplate(ssf);
         justLocked = false;
     } else if (beatTemplates.size() <= 2) {
         // restart if there is no clear correlation between beats
         if (goodBeat) {
-            std::cerr << "(2) good initial beat -> addTemplate()" << std::endl;
+            DEBUG_PRINT(std::cerr << "(2) good initial beat -> addTemplate()" << std::endl);
             addTemplate(ssf);
             if (beatTemplates.size() > 2)
-                justLocked = true; // TODO why not set? wrong compiler optimization? (is it unaware of member change?)
-            //std::cerr << "  (2) beatTemplates.size()=" << beatTemplates.size() << " justLocked=" << ((int) justLocked) << std::endl;
+                justLocked = true;
+            //DEBUG_PRINT(std::cerr << "  (2) beatTemplates.size()=" << beatTemplates.size() << " justLocked=" << ((int) justLocked) << std::endl);
         } else {
-            std::cerr << "(2) bad initial beat idx=" << idx << " -> replaceTemplate() corr=" << std::fixed << std::setw(7) << std::setprecision(4) << corr << " checkedSsf=" << checkedSsf << std::endl;
+            DEBUG_PRINT(std::cerr << "(2) bad initial beat idx=" << idx << " -> replaceTemplate() corr=" << std::fixed << std::setw(7) << std::setprecision(4) << corr << " checkedSsf=" << checkedSsf << std::endl);
             replaceTemplate(ssf);
             //badBeatRanges.clear();
             justLocked = false;
@@ -158,7 +169,7 @@ void RunningQuality::append(std::vector<double> &rawBeat, std::vector<double> &r
     } else {
         // running mode: collect bad beats, but may be OK not to restart immediately
 
-        std::cerr << "(3) running mode, good=" << ((int) goodBeat) << " justLocked=" << ((int) justLocked) << std::endl;
+        DEBUG_PRINT(std::cerr << "(3) running mode, good=" << ((int) goodBeat) << " justLocked=" << ((int) justLocked) << std::endl);
         if (goodBeat) {
             addTemplate(ssf);
         } else {