diff --git a/IO.cpp b/IO.cpp
index 9e5e155..f6c0330 100644
--- a/IO.cpp
+++ b/IO.cpp
@@ -105,12 +105,15 @@ void IO::process()
     if (m_started) {
         // Two seconds timeout
         if (m_watchdog >= 19200U) {
-/*            
-            if (m_modemState == STATE_DMR || m_modemState == STATE_P25) {
+            if (m_modemState == STATE_DMR || m_modemState == STATE_P25 || m_modemState == STATE_NXDN) {
+#if defined(DUPLEX)
+                if (m_modemState == STATE_DMR && m_tx)
+                    dmrTX.setStart(false);
+#endif
                 m_modemState = STATE_IDLE;
                 setMode(m_modemState);
             }
-*/
+
             m_watchdog = 0U;
         }
 
diff --git a/SerialPort.h b/SerialPort.h
index 81ec3ef..467905d 100644
--- a/SerialPort.h
+++ b/SerialPort.h
@@ -151,7 +151,6 @@ enum CMD_REASON_CODE {
 const uint8_t DVM_FRAME_START = 0xFEU;
 
 #define SERIAL_SPEED 115200
-#define STATE_SCAN_MAX 3
 
 // ---------------------------------------------------------------------------
 //  Class Declaration