diff --git a/MicroMDAEPiano.ino b/MicroMDAEPiano.ino
index 33fe849..6b7f6b3 100644
--- a/MicroMDAEPiano.ino
+++ b/MicroMDAEPiano.ino
@@ -166,8 +166,8 @@ elapsedMillis debug_audio_timer;
 #endif
 
 // Allocate the delay lines for left and right channels
-short l_delayline[CHORUS_DELAY_LENGTH_SAMPLES];
-short r_delayline[CHORUS_DELAY_LENGTH_SAMPLES];
+short l_delayline[MOD_DELAY_SAMPLE_BUFFER];
+short r_delayline[MOD_DELAY_SAMPLE_BUFFER];
 
 enum { VOL_MAIN, VOL_REVERB, VOL_CHORUS };
 //*************************************************************************************************
@@ -232,22 +232,33 @@ void setup()
   Serial.print(audio_block_time_us);
   Serial.println(F("us)"));
 
-  if (!modchorus_r.begin(r_delayline, CHORUS_DELAY_LENGTH_SAMPLES)) {
+  if (!modchorus_r.begin(r_delayline, MOD_DELAY_SAMPLE_BUFFER)) {
     Serial.println(F("AudioEffectModulatedDelay - right channel begin failed"));
     while (1);
   }
-  if (!modchorus_l.begin(l_delayline, CHORUS_DELAY_LENGTH_SAMPLES)) {
+  if (!modchorus_l.begin(l_delayline, MOD_DELAY_SAMPLE_BUFFER)) {
     Serial.println(F("AudioEffectModulatedDelay - left channel begin failed"));
     while (1);
   }
 
   // chorus modulation fixed
-  modulator.begin(WAVEFORM_MOD);
+  modulator.begin(MOD_WAVEFORM);
   modulator.phase(0);
   modulator.amplitude(0.0);
   modulator.offset(0.0);
-  modchorus_r.offset(0);
-  modchorus_l.offset(0);
+#ifdef DEBUG
+  Serial.print(F("Modulated delay buffer: "));
+  Serial.print(MOD_DELAY_SAMPLE_BUFFER, DEC);
+  Serial.println(F(" samples"));
+  Serial.print(F("Default delay time: "));
+  Serial.print(float(ENC_CHORUS_DELAY_DEFAULT) / 10, 2);
+  Serial.println(" ms");
+  Serial.print(F("Max delay time: "));
+  Serial.print(float(ENC_CHORUS_DELAY_MAX) / 10, 2);
+  Serial.println(F(" ms"));
+#endif
+  modchorus_r.offset(TIME_MS2SAMPLES(float(ENC_CHORUS_DELAY_DEFAULT) / 10));
+  modchorus_l.offset(TIME_MS2SAMPLES(float(ENC_CHORUS_DELAY_DEFAULT) / 10));
   // Butterworth filter, 12 db/octave
   modchorus_filter_r.setLowpass(0, 6000, 0.707);
   modchorus_filter_l.setLowpass(0, 6000, 0.707);
diff --git a/UI.hpp b/UI.hpp
index 9ac5b06..a912005 100644
--- a/UI.hpp
+++ b/UI.hpp
@@ -240,10 +240,10 @@ char* get_chorus_frequency_value_text(void)
   return (chorus_frequency_value_text1);
 }
 
-char chorus_delay_value_text1[] = "    ";
+char chorus_delay_value_text1[] = "       ";
 char* get_chorus_delay_value_text(void)
 {
-  sprintf(chorus_delay_value_text1, "%03d%%", configuration.chorus_delay);
+  sprintf(chorus_delay_value_text1, "%02.1f ms", float(configuration.chorus_delay + ENC_CHORUS_DELAY_MAX) / 10);
 
   return (chorus_delay_value_text1);
 }
@@ -2228,10 +2228,15 @@ void set_chorus_delay(uint8_t value)
     value = ENC_CHORUS_DELAY_MAX;
 #ifdef SHOW_DEBUG
   Serial.print(F("Set CHORUS_DELAY "));
-  Serial.println(value);
-#endif
-  modchorus_r.offset(value);
-  modchorus_l.offset(value);
+  Serial.print(value);
+  Serial.print(F("/"));
+  Serial.print(float(value) / 10);
+  Serial.print(F("/"));
+  Serial.print(uint16_t(TIME_MS2SAMPLES(float(value) / 10)));
+  Serial.println();
+#endif
+  modchorus_r.offset(TIME_MS2SAMPLES(float(value) / 10));
+  modchorus_l.offset(TIME_MS2SAMPLES(float(value) / 10));
   configuration.chorus_delay = value;
 }
 
@@ -2256,8 +2261,8 @@ void set_chorus_feedback(uint8_t value)
   Serial.println(value);
 #endif
   float tmp = mapfloat(float(value), ENC_CHORUS_FEEDBACK_MIN, ENC_CHORUS_FEEDBACK_MAX, 0.0, 0.5);
-  //modchorus_fbk_mixer_r.gain(0, 1.0 - tmp);
-  //modchorus_fbk_mixer_l.gain(0, 1.0 - tmp);
+  modchorus_fbk_mixer_r.gain(0, 1.0 - tmp);
+  modchorus_fbk_mixer_l.gain(0, 1.0 - tmp);
   modchorus_fbk_mixer_r.gain(1, tmp);
   modchorus_fbk_mixer_l.gain(1, tmp);
   configuration.chorus_feedback = value;
diff --git a/config.h b/config.h
index d6f6594..e5c5e76 100644
--- a/config.h
+++ b/config.h
@@ -57,9 +57,13 @@
 #define SAMPLE_RATE AUDIO_SAMPLE_RATE
 #define REDUCE_LOUDNESS 0
 #define USE_XFADE_DATA 1
+
+/* HELPER MACROS */
+#define TIME_MS2SAMPLES(x) floor(x * AUDIO_SAMPLE_RATE / 1000)
+#define SAMPLES2TIME_MS(x) float(x * 1000 / AUDIO_SAMPLE_RATE)
 // CHORUS parameters
-#define CHORUS_DELAY_LENGTH_SAMPLES (16*AUDIO_BLOCK_SAMPLES) // one AUDIO_BLOCK_SAMPLES = 2.902ms
-#define WAVEFORM_MOD WAVEFORM_TRIANGLE // WAVEFORM_SINE WAVEFORM_TRIANGLE WAVEFORM_SAWTOOTH WAVEFORM_SAWTOOTH_REVERSE
+#define MOD_DELAY_SAMPLE_BUFFER int32_t(TIME_MS2SAMPLES(10.0))
+#define MOD_WAVEFORM WAVEFORM_TRIANGLE // WAVEFORM_SINE WAVEFORM_TRIANGLE WAVEFORM_SAWTOOTH WAVEFORM_SAWTOOTH_REVERSE
 
 //*************************************************************************************************
 //* DEBUG OUTPUT SETTINGS
@@ -137,7 +141,7 @@
 //* DO NO CHANGE ANYTHING BEYOND IF YOU DON'T KNOW WHAT YOU ARE DOING !!!
 //*************************************************************************************************
 
-#define MICRO_MDAEPIANO_VERSION "0.9.8"
+#define MICRO_MDAEPIANO_VERSION "0.9.9"
 
 #define MAX_SOUNDS min(99,int((4096-EEPROM_CONFIGURATIONS)/sizeof(config_t)))
 
@@ -235,8 +239,8 @@
 #define ENC_CHORUS_FREQUENCY_DEFAULT 30
 //
 #define ENC_CHORUS_DELAY_MIN 0
-#define ENC_CHORUS_DELAY_MAX 100
-#define ENC_CHORUS_DELAY_DEFAULT 70
+#define ENC_CHORUS_DELAY_MAX uint8_t(SAMPLES2TIME_MS(float(MOD_DELAY_SAMPLE_BUFFER/2)*10))
+#define ENC_CHORUS_DELAY_DEFAULT uint8_t(float(ENC_CHORUS_DELAY_MAX/2))
 //
 #define ENC_CHORUS_INTENSITY_MIN 0
 #define ENC_CHORUS_INTENSITY_MAX 100
diff --git a/effect_modulated_delay.h b/effect_modulated_delay.h
index d697917..9c38aec 100644
--- a/effect_modulated_delay.h
+++ b/effect_modulated_delay.h
@@ -34,6 +34,9 @@
 // 140219 - correct storage class (not static)
 // 190527 - added modulation input handling (Aug 2019 by Holger Wirtz)
 
+#define TIME_MS2SAMPLES(x) floor(x * AUDIO_SAMPLE_RATE / 1000)
+#define SAMPLES2TIME_MS(x) float(x * 1000 / AUDIO_SAMPLE_RATE)
+
 class AudioEffectModulatedDelay :
   public AudioStream
 {