diff --git a/main/esp32-sequencer.c b/main/esp32-sequencer.c
index 5f6a878..8f75c7c 100644
--- a/main/esp32-sequencer.c
+++ b/main/esp32-sequencer.c
@@ -9,6 +9,7 @@
 #include "esp_log.h"
 #include "esp_random.h"
 #include "freertos/FreeRTOS.h"
+#include "freertos/portmacro.h"
 #include "freertos/queue.h"
 #include "freertos/task.h"
 #include "hal/gpio_types.h"
@@ -37,11 +38,14 @@ static QueueHandle_t control_event_queue = NULL;
 static gptimer_handle_t tap_tempo_timer = NULL;
 static gptimer_handle_t gate_timer = NULL;
 
-static const uint16_t DEBOUNCE_TIMEOUT = 20; // polling period length when debouncing in ms
+static const uint16_t DEBOUNCE_TIMEOUT = 10; // polling period length when debouncing in ms
 static uint64_t debounce_time = 0; // system time of last intterupt
 static uint8_t btn_state = 1; // state of gpio last recorded
 
+portMUX_TYPE mux = portMUX_INITIALIZER_UNLOCKED;
+
 static const uint32_t DEFAULT_BPM = 120;
+static uint16_t current_bpm = DEFAULT_BPM;
 
 #define SEQ_MAX_LEN 8
 static uint8_t sequence[SEQ_MAX_LEN] = {0};
@@ -85,14 +89,18 @@ static void tap_tempo_handler(){
     ESP_LOGI(TAG, "Starting tap tempo monitoring");
   } else { // stop the timer and calc bpm
     ESP_ERROR_CHECK(gptimer_stop(tap_tempo_timer));
-    ESP_LOGI(TAG, "Stopping tap tempo monitoring at %" PRIu64 "µs", count);
+    ESP_ERROR_CHECK(gptimer_set_raw_count(tap_tempo_timer, 0));
+    current_bpm = ms_to_bpm(count / 1000);
+    ESP_LOGI(TAG, "Stopping tap tempo monitoring at %" PRIu64 "ms", count / 1000);
   }
 }
 
 static void IRAM_ATTR gpio_isr_handler(void* arg) {
-  debounce_time = xTaskGetTickCount(); // set time of interrupt
   uint32_t gpio_num = (uint32_t)arg;
+  portENTER_CRITICAL_ISR(&mux);
+  debounce_time = xTaskGetTickCount(); // set time of interrupt
   btn_state = gpio_get_level(gpio_num); // set state
+  portEXIT_CRITICAL_ISR(&mux);
   xQueueSendFromISR(control_event_queue, &gpio_num, NULL);
 }
 
@@ -102,8 +110,10 @@ static void control_event_handler(void* arg) {
   uint64_t last_debounce_time;
   while (1) {
     // save these so we can make comparisons
+    portENTER_CRITICAL_ISR(&mux);
     last_btn_state = btn_state;
     last_debounce_time = debounce_time;
+    portEXIT_CRITICAL_ISR(&mux);
     uint8_t current_state = gpio_get_level(gpio_num);
     if (xQueueReceive(control_event_queue, &gpio_num, portMAX_DELAY)) {
       // Check if interrupt triggered stays the same for long enough
@@ -264,7 +274,7 @@ void app_main(void) {
         pulse_cv(false);
       }
       printf("%i", sequence[step]);
-      vTaskDelay(bpm_to_ms(DEFAULT_BPM)/ portTICK_PERIOD_MS);
+      vTaskDelay(bpm_to_ms(current_bpm)/ portTICK_PERIOD_MS);
     }
     printf("\n");