diff --git a/src/Main/fg_io.cxx b/src/Main/fg_io.cxx
index b3304d651..f57dac486 100644
--- a/src/Main/fg_io.cxx
+++ b/src/Main/fg_io.cxx
@@ -210,7 +210,8 @@ void fgIOInit() {
 	    p->open();
 	    global_io_list.push_back( p );
 	    if ( !p->is_enabled() ) {
-		FG_LOG( FG_IO, FG_INFO, "I/O Channel config failed." );
+		FG_LOG( FG_IO, FG_ALERT, "I/O Channel config failed." );
+		exit(-1);
 	    }
 	} else {
 	    FG_LOG( FG_IO, FG_INFO, "I/O Channel parse failed." );
@@ -253,3 +254,20 @@ void fgIOProcess() {
 	}
     }
 }
+
+
+// shutdown all I/O connections
+void fgIOShutdownAll() {
+    FGProtocol *p;
+
+    // cout << "processing I/O channels" << endl;
+
+    for ( int i = 0; i < (int)global_io_list.size(); ++i ) {
+	// cout << "  channel = " << i << endl;
+	p = global_io_list[i];
+
+	if ( p->is_enabled() ) {
+	    p->close();
+	}
+    }
+}
diff --git a/src/Main/fg_io.hxx b/src/Main/fg_io.hxx
index 6f7f55cb1..0550fdb02 100644
--- a/src/Main/fg_io.hxx
+++ b/src/Main/fg_io.hxx
@@ -36,4 +36,8 @@ void fgIOInit();
 void fgIOProcess();
 
 
+// shutdown all I/O connections
+void fgIOShutdownAll();
+
+
 #endif // _FG_IO_HXX
diff --git a/src/Main/keyboard.cxx b/src/Main/keyboard.cxx
index 69d940a1a..ba6e96092 100644
--- a/src/Main/keyboard.cxx
+++ b/src/Main/keyboard.cxx
@@ -399,7 +399,7 @@ void GLUTkey(unsigned char k, int x, int y) {
 	    //   fclose( fg_DebugOutput );
 	    // }
 	    FG_LOG( FG_INPUT, FG_ALERT, 
-		    "Program exiting normally at user request." );
+		    "Program exit requested." );
 	    ConfirmExitDialog();
 	    return;
 	}
diff --git a/src/Main/main.cxx b/src/Main/main.cxx
index 803462fd7..c0d33fe4e 100644
--- a/src/Main/main.cxx
+++ b/src/Main/main.cxx
@@ -962,7 +962,8 @@ static void fgMainLoop( void ) {
 
 	    double rpm_factor = cur_fdm_state->get_engine(0)->get_RPM() /
 		2500.0;
-	    cout << "rpm = " << cur_fdm_state->get_engine(0)->get_RPM() << endl;
+	    // cout << "rpm = " << cur_fdm_state->get_engine(0)->get_RPM()
+	    //      << endl;
 
 	    double pitch = 0.3 + rpm_factor * 3.0;
 	
@@ -970,19 +971,19 @@ static void fgMainLoop( void ) {
 	    // and sounds bad to boot.  :-)
 	    if (pitch < 0.7) { pitch = 0.7; }
 	    if (pitch > 5.0) { pitch = 5.0; }
-	    cout << "pitch = " << pitch << endl;
+	    // cout << "pitch = " << pitch << endl;
 
 	    double mp_factor =
 		cur_fdm_state->get_engine(0)->get_Manifold_Pressure() / 28;
-	    cout << "mp = " 
-		 << cur_fdm_state->get_engine(0)->get_Manifold_Pressure()
-		 << endl;
+	    // cout << "mp = " 
+	    //      << cur_fdm_state->get_engine(0)->get_Manifold_Pressure()
+	    //      << endl;
 
 	    double volume = mp_factor;
 
 	    if ( volume < 0.3 ) { volume = 0.3; }
 	    if ( volume > 2.0 ) { volume = 2.0; }
-	    cout << "volume = " << volume << endl;
+	    // cout << "volume = " << volume << endl;
 
 	    pitch_envelope.setStep  ( 0, 0.01, pitch );
 	    volume_envelope.setStep ( 0, 0.01, volume );