diff --git a/TNC/KissHardware.cpp b/TNC/KissHardware.cpp
index 8e70c6c..a0cc572 100644
--- a/TNC/KissHardware.cpp
+++ b/TNC/KissHardware.cpp
@@ -43,13 +43,13 @@ int powerOffViaUSB(void)
 namespace mobilinkd { namespace tnc { namespace kiss {
 
 #if defined(NUCLEOTNC)
-const char FIRMWARE_VERSION[] = "2.3.3";
+const char FIRMWARE_VERSION[] = "2.4.0";
 const char HARDWARE_VERSION[] = "Mobilinkd NucleoTNC";
 #elif defined(STM32L433xx)
-const char FIRMWARE_VERSION[] = "2.3.3";
+const char FIRMWARE_VERSION[] = "2.4.0";
 const char HARDWARE_VERSION[] = "Mobilinkd TNC3 2.1.1";
 #elif defined(STM32L4P5xx)
-const char FIRMWARE_VERSION[] = "2.3.3";
+const char FIRMWARE_VERSION[] = "2.4.0";
 const char HARDWARE_VERSION[] = "Mobilinkd TNC3+ Rev A";
 #endif
 Hardware& settings()
diff --git a/TNC/M17.h b/TNC/M17.h
index a903a29..df3ef9b 100644
--- a/TNC/M17.h
+++ b/TNC/M17.h
@@ -28,6 +28,7 @@ constexpr std::array<uint8_t, 2> LSF_SYNC = { 0x55, 0xF7 };
 constexpr std::array<uint8_t, 2> STREAM_SYNC = { 0xFF, 0x5D };
 constexpr std::array<uint8_t, 2> PACKET_SYNC = { 0x75, 0xFF };
 constexpr std::array<uint8_t, 2> BERT_SYNC = { 0xDF, 0x55 };
+constexpr std::array<uint8_t, 2> EOT_SYNC = { 0x55, 0x5D };
 
 inline constexpr uint16_t sync_word(std::array<uint8_t, 2> sw)
 {
diff --git a/TNC/M17Encoder.cpp b/TNC/M17Encoder.cpp
index e77700e..90a643d 100644
--- a/TNC/M17Encoder.cpp
+++ b/TNC/M17Encoder.cpp
@@ -378,6 +378,10 @@ void M17Encoder::send_stream(tnc::hdlc::IoFrame* frame, FrameType)
     frame->clear();                     // Re-use existing frame.
     for (auto c : m17::STREAM_SYNC) frame->push_back(c);
     for (auto c : m17_frame) frame->push_back(c);
+    if (state == State::IDLE)
+    {
+        for (auto c : m17::EOT_SYNC) frame->push_back(c);
+    }
 
     auto status = osMessagePut(
         m17EncoderInputQueueHandle,
@@ -570,7 +574,11 @@ void M17Encoder::encoderTask(void const*)
         HAL_IWDG_Refresh(&hiwdg);
 
         auto frame = static_cast<IoFrame*>(evt.value.p);
-        if (frame->size() != 48)
+        if (frame->size() == 50)
+        {
+            INFO("EOT");
+        }
+        else if (frame->size() != 48)
         {
             WARN("Bad frame size %u", frame->size());
         }
diff --git a/TNC/M17FrameDecoder.h b/TNC/M17FrameDecoder.h
index d3f8e63..0792ba3 100644
--- a/TNC/M17FrameDecoder.h
+++ b/TNC/M17FrameDecoder.h
@@ -425,14 +425,23 @@ struct M17FrameDecoder
         detail::to_frame(stream, output.stream);
         detail::to_bytes(output.packet, stream_segment);
 
+        stream->push_back(0); // Reserved
+
+        // RF signal quality/strength.
+        if (ber < 128) stream->push_back(255 - ber * 2);
+        else stream->push_back(0);
+
         if ((ber < 60) && (stream_segment[0] & 0x80))
         {
             INFO("EOS");
             state_ = State::LSF;
             result = DecodeResult::EOS;
         }
+
+        // Bogus CRC bytes to be dropped.
         stream->push_back(0);
         stream->push_back(0);
+
         stream->source(tnc::hdlc::IoFrame::STREAM);
         return result;
     }
diff --git a/TNC/Trellis.h b/TNC/Trellis.h
index 84b84f3..eec5808 100644
--- a/TNC/Trellis.h
+++ b/TNC/Trellis.h
@@ -1,4 +1,4 @@
-// Copyright 2020 Mobilinkd LLC.
+// Copyright 2020-2021 Mobilinkd LLC.
 
 #pragma once