diff --git a/stm32/aioc-fw/Src/ptt.h b/stm32/aioc-fw/Src/ptt.h
index aa65168..363d848 100644
--- a/stm32/aioc-fw/Src/ptt.h
+++ b/stm32/aioc-fw/Src/ptt.h
@@ -19,19 +19,19 @@ static inline void PTT_Control(uint8_t pttMask)
     __disable_irq();
 
     if (pttMask & PTT_MASK_PTT1) {
-        PTT_GPIO->BSRR |= PTT_PIN_PTT1;
+        PTT_GPIO->BSRR = PTT_PIN_PTT1;
         LED_SET(1, 1);
     } else {
-        PTT_GPIO->BRR |= PTT_PIN_PTT1;
+        PTT_GPIO->BRR = PTT_PIN_PTT1;
         LED_SET(1, 0);
     }
 
 #if AIOC_ENABLE_PTT2
     if (pttMask & PTT_MASK_PTT2) {
-        PTT_GPIO->BSRR |= PTT_PIN_PTT2;
+        PTT_GPIO->BSRR = PTT_PIN_PTT2;
         LED_SET(0, 1);
     } else {
-        PTT_GPIO->BRR |= PTT_PIN_PTT2;
+        PTT_GPIO->BRR = PTT_PIN_PTT2;
         LED_SET(0, 0);
     }
 #endif