diff --git a/radio/src/opentx.h b/radio/src/opentx.h
index 3d3cc3ae7..ddfcb9830 100644
--- a/radio/src/opentx.h
+++ b/radio/src/opentx.h
@@ -502,6 +502,7 @@ void evalFlightModeMixes(uint8_t mode, uint8_t tick10ms);
 void evalMixes(uint8_t tick10ms);
 void doMixerCalculations();
 void doMixerPeriodicUpdates();
+void scheduleNextMixerCalculation(uint8_t module, uint32_t period_ms);
 
 void checkTrims();
 extern uint8_t currentBacklightBright;
diff --git a/radio/src/pulses/pulses.cpp b/radio/src/pulses/pulses.cpp
index 7292bb200..810fd9378 100755
--- a/radio/src/pulses/pulses.cpp
+++ b/radio/src/pulses/pulses.cpp
@@ -241,8 +241,12 @@ void enablePulsesExternalModule(uint8_t protocol)
     case PROTOCOL_CHANNELS_DSM2_LP45:
     case PROTOCOL_CHANNELS_DSM2_DSM2:
     case PROTOCOL_CHANNELS_DSM2_DSMX:
+#if defined(PCBSKY9X)
+      extmoduleSerialStart(DSM2_BAUDRATE, DSM2_PERIOD * 2000, false);
+#else
       extmoduleSerialStart();
       mixerSchedulerSetPeriod(EXTERNAL_MODULE, DSM2_PERIOD);
+#endif
       break;
 #endif
 
@@ -274,15 +278,23 @@ void enablePulsesExternalModule(uint8_t protocol)
 
 #if defined(MULTIMODULE)
     case PROTOCOL_CHANNELS_MULTIMODULE:
+#if defined(PCBSKY9X)
+      extmoduleSerialStart(MULTIMODULE_BAUDRATE, MULTIMODULE_PERIOD * 2000, true);
+#else
       extmoduleSerialStart();
       mixerSchedulerSetPeriod(EXTERNAL_MODULE, MULTIMODULE_PERIOD);
+#endif
       break;
 #endif
 
 #if defined(SBUS)
     case PROTOCOL_CHANNELS_SBUS:
+#if defined(PCBSKY9X)
+      extmoduleSerialStart(SBUS_BAUDRATE, SBUS_PERIOD_HALF_US, false);
+#else
       extmoduleSerialStart();
       mixerSchedulerSetPeriod(EXTERNAL_MODULE, SBUS_PERIOD);
+#endif
       break;
 #endif
 
@@ -314,12 +326,18 @@ bool setupPulsesExternalModule(uint8_t protocol)
 #if defined(PXX1)
     case PROTOCOL_CHANNELS_PXX1_PULSES:
       extmodulePulsesData.pxx.setupFrame(EXTERNAL_MODULE);
+#if defined(PCBSKY9X)
+      scheduleNextMixerCalculation(EXTERNAL_MODULE, PXX_PULSES_PERIOD);
+#endif
       return true;
 #endif
 
 #if defined(PXX1) && defined(HARDWARE_EXTERNAL_MODULE_SIZE_SML)
     case PROTOCOL_CHANNELS_PXX1_SERIAL:
       extmodulePulsesData.pxx_uart.setupFrame(EXTERNAL_MODULE);
+#if defined(PCBSKY9X)
+      scheduleNextMixerCalculation(EXTERNAL_MODULE, EXTMODULE_PXX1_SERIAL_PERIOD);
+#endif
       return true;
 #endif
 
@@ -327,13 +345,18 @@ bool setupPulsesExternalModule(uint8_t protocol)
     case PROTOCOL_CHANNELS_PXX2_HIGHSPEED:
     case PROTOCOL_CHANNELS_PXX2_LOWSPEED:
       extmodulePulsesData.pxx2.setupFrame(EXTERNAL_MODULE);
+#if defined(PCBSKY9X)
+      sheduleNextMixerCalculation(EXTERNAL_MODULE, PXX2_PERIOD);
+#endif
       return true;
 #endif
 
 #if defined(SBUS)
     case PROTOCOL_CHANNELS_SBUS:
       setupPulsesSbus();
-
+#if defined(PCBSKY9X)
+      scheduleNextMixerCalculation(EXTERNAL_MODULE, SBUS_PERIOD);
+#endif
       // SBUS_PERIOD is not a constant! It can be set from UI
       mixerSchedulerSetPeriod(EXTERNAL_MODULE, SBUS_PERIOD);
       return true;
@@ -344,6 +367,9 @@ bool setupPulsesExternalModule(uint8_t protocol)
     case PROTOCOL_CHANNELS_DSM2_DSM2:
     case PROTOCOL_CHANNELS_DSM2_DSMX:
       setupPulsesDSM2();
+#if defined(PCBSKY9X)
+      scheduleNextMixerCalculation(EXTERNAL_MODULE, DSM2_PERIOD);
+#endif
       return true;
 #endif
 
@@ -356,6 +382,9 @@ bool setupPulsesExternalModule(uint8_t protocol)
       else
         mixerSchedulerSetPeriod(EXTERNAL_MODULE, CROSSFIRE_PERIOD);
       setupPulsesCrossfire();
+#if defined(PCBSKY9X)
+      scheduleNextMixerCalculation(EXTERNAL_MODULE, CROSSFIRE_PERIOD);
+#endif
       return true;
     }
 #endif
@@ -369,6 +398,9 @@ bool setupPulsesExternalModule(uint8_t protocol)
       else
         mixerSchedulerSetPeriod(EXTERNAL_MODULE, GHOST_PERIOD);
       setupPulsesGhost();
+#if defined(PCBSKPCBSKY9X)
+      scheduleNextMixerCalculation(EXTERNAL_MODULE, GHOST_PERIOD);
+#endif
       return true;
     }
 #endif
@@ -382,6 +414,9 @@ bool setupPulsesExternalModule(uint8_t protocol)
       else
         mixerSchedulerSetPeriod(EXTERNAL_MODULE, MULTIMODULE_PERIOD);
       setupPulsesMultiExternalModule();
+#if defined(PCBSKY9X)
+      scheduleNextMixerCalculation(EXTERNAL_MODULE, MULTIMODULE_PERIOD);
+#endif
       return true;
     }
 #endif
@@ -389,12 +424,18 @@ bool setupPulsesExternalModule(uint8_t protocol)
 #if defined(PPM)
     case PROTOCOL_CHANNELS_PPM:
       setupPulsesPPMExternalModule();
+#if defined(PCBSKY9X)
+      scheduleNextMixerCalculation(EXTERNAL_MODULE, PPM_PERIOD(EXTERNAL_MODULE));
+#endif
       return true;
 #endif
 
 #if defined(AFHDS3)
     case PROTOCOL_CHANNELS_AFHDS3:
       extmodulePulsesData.afhds3.setupFrame();
+#if defined(PCBSKY9X)
+      scheduleNextMixerCalculation(EXTERNAL_MODULE, AFHDS3_COMMAND_TIMEOUT);
+#endif
       return true;
 #endif
 
diff --git a/radio/src/tasks.cpp b/radio/src/tasks.cpp
index d0aa8e3d2..97f78c972 100644
--- a/radio/src/tasks.cpp
+++ b/radio/src/tasks.cpp
@@ -118,7 +118,9 @@ TASK_FUNCTION(mixerTask)
   s_pulses_paused = true;
 
   mixerSchedulerInit();
+#if !defined(PCBSKY9X)
   mixerSchedulerStart();
+#endif
 
   while (true) {
 #if defined(SBUS_TRAINER)
@@ -142,8 +144,10 @@ TASK_FUNCTION(mixerTask)
     GPIO_ResetBits(EXTMODULE_TX_GPIO, EXTMODULE_TX_GPIO_PIN);
 #endif
 
+#if !defined(PCBSKY9X)
     // re-enable trigger
     mixerSchedulerEnableTrigger();
+#endif
 
 #if defined(SIMU)
     if (pwrCheck() == e_power_off) {
@@ -164,7 +168,11 @@ TASK_FUNCTION(mixerTask)
       doMixerCalculations();
 
       // TODO: fix runMask
+#if defined(PCBSKY9X)
+      sendSynchronousPulses(1 << EXTERNAL_MODULE);
+#else
       sendSynchronousPulses((1 << INTERNAL_MODULE) | (1 << EXTERNAL_MODULE));
+#endif
 
       doMixerPeriodicUpdates();
 
@@ -200,12 +208,32 @@ TASK_FUNCTION(mixerTask)
       // TODO:
       // - check the cause of timeouts when switching
       //    between protocols with multi-proto RF
+#if defined(DEBUG)
       if (timeout)
         serialPrint("mix sched timeout!");
+#endif
     }
   }
 }
 
+void scheduleNextMixerCalculation(uint8_t module, uint32_t period_ms)
+{
+  // Schedule next mixer calculation time,
+
+  if (isModuleSynchronous(module)) {
+    nextMixerTime[module] += period_ms / RTOS_MS_PER_TICK;
+    if (nextMixerTime[module] < RTOS_GET_TIME()) {
+      // we are late ... let's add some small delay
+      nextMixerTime[module] = (uint32_t) RTOS_GET_TIME() + (period_ms / RTOS_MS_PER_TICK);
+    }
+  }
+  else {
+    // for now assume mixer calculation takes 2 ms.
+    nextMixerTime[module] = (uint32_t) RTOS_GET_TIME() + (period_ms / RTOS_MS_PER_TICK);
+  }
+
+  DEBUG_TIMER_STOP(debugTimerMixerCalcToUsage);
+}
 
 #define MENU_TASK_PERIOD_TICKS         (50 / RTOS_MS_PER_TICK)    // 50ms
 
diff --git a/radio/src/telemetry/multi.cpp b/radio/src/telemetry/multi.cpp
index 1cb560b14..624effbba 100644
--- a/radio/src/telemetry/multi.cpp
+++ b/radio/src/telemetry/multi.cpp
@@ -252,8 +252,9 @@ static void processMultiSyncPacket(const uint8_t * data, uint8_t module)
   //   inputLag -= refreshRate;
 
   status.update(refreshRate, inputLag);
-
+#if defined(DEBUG)
   serialPrint("MP ADJ: R %d, L %04d", refreshRate, inputLag);
+#endif
 }
 
 #if defined(PCBTARANIS) || defined(PCBHORUS)