diff --git a/GITHUB_SHA.h b/GITHUB_SHA.h
index 75a9be6..54a7905 100644
--- a/GITHUB_SHA.h
+++ b/GITHUB_SHA.h
@@ -1 +1 @@
-#define GITHUB_SHA "devel-202302281422Z"
+#define GITHUB_SHA "devel-202303071416Z"
diff --git a/MotorDriver.cpp b/MotorDriver.cpp
index a6a1766..0236215 100644
--- a/MotorDriver.cpp
+++ b/MotorDriver.cpp
@@ -75,6 +75,23 @@ MotorDriver::MotorDriver(int16_t power_pin, byte signal_pin, byte signal_pin2, i
     dualSignal=true;
     getFastPin(F("SIG2"),signalPin2,fastSignalPin2);
     pinMode(signalPin2, OUTPUT);
+
+    fastSignalPin2.shadowinout = NULL;
+    if (HAVE_PORTA(fastSignalPin2.inout == &PORTA)) {
+      DIAG(F("Found PORTA pin %d"),signalPin2);
+      fastSignalPin2.shadowinout = fastSignalPin2.inout;
+      fastSignalPin2.inout = &shadowPORTA;
+    }
+    if (HAVE_PORTB(fastSignalPin2.inout == &PORTB)) {
+      DIAG(F("Found PORTB pin %d"),signalPin2);
+      fastSignalPin2.shadowinout = fastSignalPin2.inout;
+      fastSignalPin2.inout = &shadowPORTB;
+    }
+    if (HAVE_PORTC(fastSignalPin2.inout == &PORTC)) {
+      DIAG(F("Found PORTC pin %d"),signalPin2);
+      fastSignalPin2.shadowinout = fastSignalPin2.inout;
+      fastSignalPin2.inout = &shadowPORTC;
+    }
   }
   else dualSignal=false; 
   
diff --git a/version.h b/version.h
index 789ef2c..a4520fb 100644
--- a/version.h
+++ b/version.h
@@ -4,7 +4,8 @@
 #include "StringFormatter.h"
 
 
-#define VERSION "4.2.22"
+#define VERSION "4.2.23"
+// 4.2.23 - Bugfix signalpin2 was not set up in shadow port
 // 4.2.22 - Implement broadcast of Track Manager changes
 // 4.2.21 - Implement non-blocking I2C for EX-IOExpander device driver
 // 4.2.20 - <JG> & <JI> commands for multi-track gauges