diff --git a/radio/src/io/frsky_firmware_update.cpp b/radio/src/io/frsky_firmware_update.cpp
index cf8aacca1..7fcedbd86 100644
--- a/radio/src/io/frsky_firmware_update.cpp
+++ b/radio/src/io/frsky_firmware_update.cpp
@@ -165,6 +165,8 @@ const uint8_t * FrskyDeviceFirmwareUpdate::readHalfDuplexFrame(uint32_t timeout)
 
 const uint8_t * FrskyDeviceFirmwareUpdate::readFrame(uint32_t timeout)
 {
+  RTOS_WAIT_MS(1);
+
   switch(module) {
 #if defined(INTMODULE_USART)
     case INTERNAL_MODULE:
@@ -238,7 +240,10 @@ void FrskyDeviceFirmwareUpdate::sendFrame()
 const char * FrskyDeviceFirmwareUpdate::sendPowerOn()
 {
   state = SPORT_POWERUP_REQ;
-  waitState(SPORT_IDLE, 50); // Wait 50ms and clear the fifo
+
+  RTOS_WAIT_MS(50);
+  telemetryClearFifo();
+
   for (int i=0; i<10; i++) {
     // max 10 attempts
     startFrame(PRIM_REQ_POWERUP);
@@ -268,7 +273,9 @@ const char * FrskyDeviceFirmwareUpdate::sendPowerOn()
 
 const char * FrskyDeviceFirmwareUpdate::sendReqVersion()
 {
-  waitState(SPORT_IDLE, 20); // Clear the fifo
+  RTOS_WAIT_MS(20);
+  telemetryClearFifo();
+
   state = SPORT_VERSION_REQ;
   for (int i=0; i<10; i++) {
     // max 10 attempts
@@ -299,7 +306,9 @@ const char * FrskyDeviceFirmwareUpdate::uploadFile(const char * filename)
     }
   }
 
-  waitState(SPORT_IDLE, 200); // Clear the fifo
+  RTOS_WAIT_MS(200);
+  telemetryClearFifo();
+
   state = SPORT_DATA_TRANSFER;
   startFrame(PRIM_CMD_DOWNLOAD);
   sendFrame();
@@ -385,11 +394,10 @@ void FrskyDeviceFirmwareUpdate::flashFirmware(const char * filename)
   EXTERNAL_MODULE_OFF();
   SPORT_UPDATE_POWER_OFF();
 
-  waitState(SPORT_IDLE, 500); // Clear the fifo
-
   /* wait 2s off */
   watchdogSuspend(2000);
   RTOS_WAIT_MS(2000);
+  telemetryClearFifo();
 
   if (intPwr) {
     INTERNAL_MODULE_ON();
diff --git a/radio/src/targets/horus/board.h b/radio/src/targets/horus/board.h
index 719c5c124..ea4d2604e 100644
--- a/radio/src/targets/horus/board.h
+++ b/radio/src/targets/horus/board.h
@@ -600,6 +600,7 @@ void telemetryPortSetDirectionOutput(void);
 void sportSendByte(uint8_t byte);
 void sportSendBuffer(const uint8_t * buffer, uint32_t count);
 uint8_t telemetryGetByte(uint8_t * byte);
+void telemetryClearFifo();
 extern uint32_t telemetryErrors;
 
 // Sport update driver
diff --git a/radio/src/targets/horus/telemetry_driver.cpp b/radio/src/targets/horus/telemetry_driver.cpp
index f9e278da6..6d9276ef1 100644
--- a/radio/src/targets/horus/telemetry_driver.cpp
+++ b/radio/src/targets/horus/telemetry_driver.cpp
@@ -235,3 +235,13 @@ uint8_t telemetryGetByte(uint8_t * byte)
   return telemetryNoDMAFifo.pop(*byte);
 #endif
 }
+
+void telemetryClearFifo()
+{
+#if defined(PCBX12S)
+  telemetryDMAFifo.clear();
+#endif
+
+  telemetryNoDMAFifo.clear();
+}
+
diff --git a/radio/src/targets/taranis/board.h b/radio/src/targets/taranis/board.h
index 6d26506b9..fa3b32f8b 100644
--- a/radio/src/targets/taranis/board.h
+++ b/radio/src/targets/taranis/board.h
@@ -696,6 +696,7 @@ void telemetryPortSetDirectionOutput(void);
 void sportSendByte(uint8_t byte);
 void sportSendBuffer(const uint8_t * buffer, uint32_t count);
 uint8_t telemetryGetByte(uint8_t * byte);
+void telemetryClearFifo();
 extern uint32_t telemetryErrors;
 
 // PCBREV driver
diff --git a/radio/src/targets/taranis/telemetry_driver.cpp b/radio/src/targets/taranis/telemetry_driver.cpp
index 8a3bfb3f6..dc82fcd81 100644
--- a/radio/src/targets/taranis/telemetry_driver.cpp
+++ b/radio/src/targets/taranis/telemetry_driver.cpp
@@ -198,3 +198,8 @@ uint8_t telemetryGetByte(uint8_t * byte)
   return telemetryFifo.pop(*byte);
 #endif
 }
+
+void telemetryClearFifo()
+{
+  telemetryFifo.clear();
+}