diff --git a/src/modules/LR11x0/LR11x0.cpp b/src/modules/LR11x0/LR11x0.cpp
index 52c270cc..bcef4d0b 100644
--- a/src/modules/LR11x0/LR11x0.cpp
+++ b/src/modules/LR11x0/LR11x0.cpp
@@ -1328,7 +1328,7 @@ int16_t LR11x0::irqRxDoneRxTimeout(uint32_t &irqFlags, uint32_t &irqMask) {
   return(RADIOLIB_ERR_NONE);
 }
 
-bool LR11x0::isIrqSet(uint8_t irq) {
+int16_t LR11x0::checkIrq(uint8_t irq) {
   uint16_t flags = getIrqStatus();
   switch(irq) {
     case RADIOLIB_IRQ_TX_DONE:
@@ -1351,12 +1351,10 @@ bool LR11x0::isIrqSet(uint8_t irq) {
       return(flags & RADIOLIB_LR11X0_IRQ_CAD_DETECTED);
     case RADIOLIB_IRQ_TIMEOUT:
       return(flags & RADIOLIB_LR11X0_IRQ_TIMEOUT);
-    case RADIOLIB_IRQ_LR_FHSS_HOP:
-      return(flags & RADIOLIB_LR11X0_IRQ_LR_FHSS_HOP);
     default:
-      return(false);
+      return(RADIOLIB_ERR_UNSUPPORTED);
   }
-  return(false);
+  return(RADIOLIB_ERR_UNSUPPORTED);
 }
 
 uint8_t LR11x0::randomByte() {
diff --git a/src/modules/LR11x0/LR11x0.h b/src/modules/LR11x0/LR11x0.h
index 1f9fedbc..dffac085 100644
--- a/src/modules/LR11x0/LR11x0.h
+++ b/src/modules/LR11x0/LR11x0.h
@@ -1232,7 +1232,7 @@ class LR11x0: public PhysicalLayer {
       \brief Check whether a specific IRQ bit is set (e.g. RxTimeout, CadDone).
       \returns Whether requested IRQ is set.
     */
-    bool isIrqSet(uint8_t irq) override;
+    int16_t checkIrq(uint8_t irq) override;
 
     /*!
       \brief Get one truly random byte from RSSI noise.
diff --git a/src/modules/SX126x/SX126x.cpp b/src/modules/SX126x/SX126x.cpp
index 12b6f5f0..1c2a9e48 100644
--- a/src/modules/SX126x/SX126x.cpp
+++ b/src/modules/SX126x/SX126x.cpp
@@ -1466,7 +1466,7 @@ int16_t SX126x::irqRxDoneRxTimeout(uint32_t &irqFlags, uint32_t &irqMask) {
   return(RADIOLIB_ERR_NONE);
 }
 
-bool SX126x::isIrqSet(uint8_t irq) {
+int16_t SX126x::checkIrq(uint8_t irq) {
   uint16_t flags = getIrqStatus();
   switch(irq) {
     case RADIOLIB_IRQ_TX_DONE:
@@ -1489,12 +1489,10 @@ bool SX126x::isIrqSet(uint8_t irq) {
       return(flags & RADIOLIB_SX126X_IRQ_CAD_DETECTED);
     case RADIOLIB_IRQ_TIMEOUT:
       return(flags & RADIOLIB_SX126X_IRQ_TIMEOUT);
-    case RADIOLIB_IRQ_LR_FHSS_HOP:
-      return(flags & RADIOLIB_SX126X_IRQ_LR_FHSS_HOP);
     default:
-      return(false);
+      return(RADIOLIB_ERR_UNSUPPORTED);
   }
-  return(false);
+  return(RADIOLIB_ERR_UNSUPPORTED);
 }
 
 int16_t SX126x::implicitHeader(size_t len) {
diff --git a/src/modules/SX126x/SX126x.h b/src/modules/SX126x/SX126x.h
index 1a4fd2ca..68598650 100644
--- a/src/modules/SX126x/SX126x.h
+++ b/src/modules/SX126x/SX126x.h
@@ -1000,7 +1000,7 @@ class SX126x: public PhysicalLayer {
       \brief Check whether a specific IRQ bit is set (e.g. RxTimeout, CadDone).
       \returns Whether requested IRQ is set.
     */
-    bool isIrqSet(uint8_t irq) override;
+    int16_t checkIrq(uint8_t irq) override;
 
     /*!
       \brief Set implicit header mode for future reception/transmission.
diff --git a/src/modules/SX127x/SX127x.cpp b/src/modules/SX127x/SX127x.cpp
index 621d2ee8..7cc33c9f 100644
--- a/src/modules/SX127x/SX127x.cpp
+++ b/src/modules/SX127x/SX127x.cpp
@@ -1302,7 +1302,7 @@ int16_t SX127x::irqRxDoneRxTimeout(uint32_t &irqFlags, uint32_t &irqMask) {
   return(RADIOLIB_ERR_NONE);
 }
 
-bool SX127x::isIrqSet(uint8_t irq) {
+int16_t SX127x::checkIrq(uint8_t irq) {
   uint16_t flags = getIRQFlags();
   switch(irq) {
     case RADIOLIB_IRQ_TX_DONE:
@@ -1320,9 +1320,9 @@ bool SX127x::isIrqSet(uint8_t irq) {
     case RADIOLIB_IRQ_TIMEOUT:
       return(flags & RADIOLIB_SX127X_CLEAR_IRQ_FLAG_RX_TIMEOUT);
     default:
-      return(false);
+      return(RADIOLIB_ERR_UNSUPPORTED);
   }
-  return(false);
+  return(RADIOLIB_ERR_UNSUPPORTED);
 }
 
 int16_t SX127x::setCrcFiltering(bool enable) {
diff --git a/src/modules/SX127x/SX127x.h b/src/modules/SX127x/SX127x.h
index 34dba0b8..c00cd42f 100644
--- a/src/modules/SX127x/SX127x.h
+++ b/src/modules/SX127x/SX127x.h
@@ -1076,7 +1076,7 @@ class SX127x: public PhysicalLayer {
       \brief Check whether a specific IRQ bit is set (e.g. RxTimeout, CadDone).
       \returns Whether requested IRQ is set.
     */
-    bool isIrqSet(uint8_t irq) override;
+    int16_t checkIrq(uint8_t irq) override;
 
     /*!
       \brief Enable CRC filtering and generation.
diff --git a/src/modules/SX128x/SX128x.cpp b/src/modules/SX128x/SX128x.cpp
index 35a1d46b..fb9ed328 100644
--- a/src/modules/SX128x/SX128x.cpp
+++ b/src/modules/SX128x/SX128x.cpp
@@ -638,7 +638,7 @@ int16_t SX128x::readData(uint8_t* data, size_t len) {
   return(state);
 }
 
-bool SX128x::isIrqSet(uint8_t irq) {
+int16_t SX128x::checkIrq(uint8_t irq) {
   uint16_t flags = getIrqStatus();
   switch(irq) {
     case RADIOLIB_IRQ_TX_DONE:
@@ -649,8 +649,6 @@ bool SX128x::isIrqSet(uint8_t irq) {
       return(flags & RADIOLIB_SX128X_IRQ_PREAMBLE_DETECTED);
     case RADIOLIB_IRQ_SYNC_WORD_VALID:
       return(flags & RADIOLIB_SX128X_IRQ_SYNC_WORD_VALID);
-    case RADIOLIB_IRQ_SYNC_WORD_ERROR:
-      return(flags & RADIOLIB_SX128X_IRQ_SYNC_WORD_ERROR);
     case RADIOLIB_IRQ_HEADER_VALID:
       return(flags & RADIOLIB_SX128X_IRQ_HEADER_VALID);
     case RADIOLIB_IRQ_HEADER_ERR:
@@ -664,9 +662,9 @@ bool SX128x::isIrqSet(uint8_t irq) {
     case RADIOLIB_IRQ_TIMEOUT:
       return(flags & RADIOLIB_SX128X_IRQ_RX_TX_TIMEOUT);
     default:
-      return(false);
+      return(RADIOLIB_ERR_UNSUPPORTED);
   }
-  return(false);
+  return(RADIOLIB_ERR_UNSUPPORTED);
 }
 
 int16_t SX128x::startChannelScan() {
diff --git a/src/modules/SX128x/SX128x.h b/src/modules/SX128x/SX128x.h
index 805c0579..43c1f412 100644
--- a/src/modules/SX128x/SX128x.h
+++ b/src/modules/SX128x/SX128x.h
@@ -580,7 +580,7 @@ class SX128x: public PhysicalLayer {
       \brief Check whether a specific IRQ bit is set (e.g. RxTimeout, CadDone).
       \returns Whether requested IRQ is set.
     */
-    bool isIrqSet(uint8_t irq) override;
+    int16_t checkIrq(uint8_t irq) override;
 
     /*!
       \brief Interrupt-driven channel activity detection method. DIO1 will be activated
diff --git a/src/protocols/LoRaWAN/LoRaWAN.cpp b/src/protocols/LoRaWAN/LoRaWAN.cpp
index 92b0b2ee..c5739cc8 100644
--- a/src/protocols/LoRaWAN/LoRaWAN.cpp
+++ b/src/protocols/LoRaWAN/LoRaWAN.cpp
@@ -1226,7 +1226,11 @@ int16_t LoRaWANNode::downlinkCommon() {
     RADIOLIB_DEBUG_PROTOCOL_PRINTLN("Closing Rx%d window", i+1);
 
     // check if the IRQ bit for Rx Timeout is set
-    if(!this->phyLayer->isIrqSet(RADIOLIB_IRQ_TIMEOUT)) {
+    state = this->phyLayer->checkIrq(RADIOLIB_IRQ_TIMEOUT);
+    if(state == RADIOLIB_ERR_UNSUPPORTED) {
+      return(state);
+    }
+    if(state == 0) {
       break;
 
     } else if(i == 0) {
@@ -1248,7 +1252,11 @@ int16_t LoRaWANNode::downlinkCommon() {
   this->rxDelayEnd = mod->hal->millis();
 
   // if we got here due to a timeout, stop ongoing activities
-  if(this->phyLayer->isIrqSet(RADIOLIB_IRQ_TIMEOUT)) {
+  state = this->phyLayer->checkIrq(RADIOLIB_IRQ_TIMEOUT);
+  if(state == RADIOLIB_ERR_UNSUPPORTED) {
+    return(state);
+  }
+  if(state == 1) {
     this->phyLayer->standby();  // TODO check: this should be done automagically due to RxSingle?
     if(this->modulation == RADIOLIB_LORAWAN_MODULATION_LORA) {
       this->phyLayer->invertIQ(false);
diff --git a/src/protocols/PhysicalLayer/PhysicalLayer.cpp b/src/protocols/PhysicalLayer/PhysicalLayer.cpp
index 02fc12c5..6953447c 100644
--- a/src/protocols/PhysicalLayer/PhysicalLayer.cpp
+++ b/src/protocols/PhysicalLayer/PhysicalLayer.cpp
@@ -316,9 +316,9 @@ int16_t PhysicalLayer::irqRxDoneRxTimeout(uint32_t &irqFlags, uint32_t &irqMask)
   return(RADIOLIB_ERR_UNSUPPORTED);
 }
 
-bool PhysicalLayer::isIrqSet(uint8_t irq) {
+int16_t PhysicalLayer::checkIrq(uint8_t irq) {
   (void)irq;
-  return(false);
+  return(RADIOLIB_ERR_UNSUPPORTED);
 }
 
 int16_t PhysicalLayer::startChannelScan() {
diff --git a/src/protocols/PhysicalLayer/PhysicalLayer.h b/src/protocols/PhysicalLayer/PhysicalLayer.h
index b6165647..408408ae 100644
--- a/src/protocols/PhysicalLayer/PhysicalLayer.h
+++ b/src/protocols/PhysicalLayer/PhysicalLayer.h
@@ -9,14 +9,12 @@
 #define RADIOLIB_IRQ_RX_DONE                                    0x01
 #define RADIOLIB_IRQ_PREAMBLE_DETECTED                          0x02
 #define RADIOLIB_IRQ_SYNC_WORD_VALID                            0x03
-#define RADIOLIB_IRQ_SYNC_WORD_ERROR                            0x04
-#define RADIOLIB_IRQ_HEADER_VALID                               0x05
-#define RADIOLIB_IRQ_HEADER_ERR                                 0x06
-#define RADIOLIB_IRQ_CRC_ERR                                    0x07
-#define RADIOLIB_IRQ_CAD_DONE                                   0x08
-#define RADIOLIB_IRQ_CAD_DETECTED                               0x09
-#define RADIOLIB_IRQ_TIMEOUT                                    0x0A
-#define RADIOLIB_IRQ_LR_FHSS_HOP                                0x0B
+#define RADIOLIB_IRQ_HEADER_VALID                               0x04
+#define RADIOLIB_IRQ_HEADER_ERR                                 0x05
+#define RADIOLIB_IRQ_CRC_ERR                                    0x06
+#define RADIOLIB_IRQ_CAD_DONE                                   0x07
+#define RADIOLIB_IRQ_CAD_DETECTED                               0x08
+#define RADIOLIB_IRQ_TIMEOUT                                    0x09
 
 /*!
   \struct LoRaRate_t
@@ -379,7 +377,7 @@ class PhysicalLayer {
       \brief Check whether a specific IRQ bit is set (e.g. RxTimeout, CadDone).
       \returns Whether requested IRQ is set.
     */
-    virtual bool isIrqSet(uint8_t irq);
+    virtual int16_t checkIrq(uint8_t irq);
 
     /*!
       \brief Interrupt-driven channel activity detection method. Interrupt will be activated