diff --git a/src/demod/DemodulatorThread.cpp b/src/demod/DemodulatorThread.cpp
index 8bcee24..e67a7b8 100644
--- a/src/demod/DemodulatorThread.cpp
+++ b/src/demod/DemodulatorThread.cpp
@@ -113,9 +113,9 @@ void DemodulatorThread::threadMain() {
             audioResampler = inp->audioResampler;
             stereoResampler = inp->stereoResampler;
 
-            ampmodem_reset(demodAM_USB);
-            ampmodem_reset(demodAM_LSB);
-            ampmodem_reset(demodAM_DSB_CSP);
+            if (demodAM) {
+                ampmodem_reset(demodAM);
+            }
             freqdem_reset(demodFM);
         }
 
@@ -352,18 +352,23 @@ void DemodulatorThread::threadMain() {
             if (newDemodType != DEMOD_TYPE_NULL) {
                 switch (newDemodType) {
                 case DEMOD_TYPE_FM:
+                    freqdem_reset(demodFM);
                     break;
                 case DEMOD_TYPE_LSB:
                     demodAM = demodAM_USB;
+                    ampmodem_reset(demodAM);
                     break;
                 case DEMOD_TYPE_USB:
                     demodAM = demodAM_LSB;
+                    ampmodem_reset(demodAM);
                     break;
                 case DEMOD_TYPE_DSB:
                     demodAM = demodAM_DSB;
+                    ampmodem_reset(demodAM);
                     break;
                 case DEMOD_TYPE_AM:
                     demodAM = demodAM_DSB_CSP;
+                    ampmodem_reset(demodAM);
                     break;
                 }
                 demodulatorType = newDemodType;
diff --git a/src/visual/TuningCanvas.cpp b/src/visual/TuningCanvas.cpp
index c8acc42..eec0293 100644
--- a/src/visual/TuningCanvas.cpp
+++ b/src/visual/TuningCanvas.cpp
@@ -95,7 +95,6 @@ void TuningCanvas::OnMouseMoved(wxMouseEvent& event) {
 
 void TuningCanvas::OnMouseDown(wxMouseEvent& event) {
     InteractiveCanvas::OnMouseDown(event);
-    mouseTracker.setHorizDragLock(true);
     mouseTracker.setVertDragLock(true);
 
     uxDown = 2.0 * (mouseTracker.getMouseX() - 0.5);
@@ -110,7 +109,6 @@ void TuningCanvas::OnMouseWheelMoved(wxMouseEvent& event) {
 
 void TuningCanvas::OnMouseReleased(wxMouseEvent& event) {
     InteractiveCanvas::OnMouseReleased(event);
-    mouseTracker.setHorizDragLock(false);
     mouseTracker.setVertDragLock(false);
     SetCursor (wxCURSOR_SIZEWE);
 }
diff --git a/src/visual/WaterfallCanvas.cpp b/src/visual/WaterfallCanvas.cpp
index 8a2d3a9..9a502db 100644
--- a/src/visual/WaterfallCanvas.cpp
+++ b/src/visual/WaterfallCanvas.cpp
@@ -680,7 +680,11 @@ void WaterfallCanvas::OnMouseWheelMoved(wxMouseEvent& event) {
     InteractiveCanvas::OnMouseWheelMoved(event);
     float movement = (float)event.GetWheelRotation() / (float)event.GetLinesPerAction();
 
+#ifdef __APPLE__
     mouseZoom = 1.0f - movement/100.0f;
+#else
+    mouseZoom = 1.0f - movement/1000.0f;
+#endif
 }
 
 void WaterfallCanvas::OnMouseReleased(wxMouseEvent& event) {