diff --git a/dgl/ImageKnob.hpp b/dgl/ImageKnob.hpp
index b9a62532..a7a7e69e 100644
--- a/dgl/ImageKnob.hpp
+++ b/dgl/ImageKnob.hpp
@@ -76,6 +76,7 @@ private:
     float fValue;
     float fValueDef;
     float fValueTmp;
+    bool  fUsingDefault;
     bool  fUsingLog;
     Orientation fOrientation;
 
diff --git a/dgl/src/ImageKnob.cpp b/dgl/src/ImageKnob.cpp
index 3953646c..33a1b8ab 100644
--- a/dgl/src/ImageKnob.cpp
+++ b/dgl/src/ImageKnob.cpp
@@ -32,6 +32,7 @@ ImageKnob::ImageKnob(Window& parent, const Image& image, Orientation orientation
       fValue(0.5f),
       fValueDef(fValue),
       fValueTmp(fValue),
+      fUsingDefault(false),
       fUsingLog(false),
       fOrientation(orientation),
       fRotationAngle(0),
@@ -58,6 +59,7 @@ ImageKnob::ImageKnob(Widget* widget, const Image& image, Orientation orientation
       fValue(0.5f),
       fValueDef(fValue),
       fValueTmp(fValue),
+      fUsingDefault(false),
       fUsingLog(false),
       fOrientation(orientation),
       fRotationAngle(0),
@@ -84,6 +86,7 @@ ImageKnob::ImageKnob(const ImageKnob& imageKnob)
       fValue(imageKnob.fValue),
       fValueDef(imageKnob.fValueDef),
       fValueTmp(fValue),
+      fUsingDefault(imageKnob.fUsingDefault),
       fUsingLog(imageKnob.fUsingLog),
       fOrientation(imageKnob.fOrientation),
       fRotationAngle(imageKnob.fRotationAngle),
@@ -131,6 +134,7 @@ float ImageKnob::getValue() const noexcept
 void ImageKnob::setDefault(float value) noexcept
 {
     fValueDef = value;
+    fUsingDefault = true;
 }
 
 void ImageKnob::setRange(float min, float max) noexcept
@@ -162,11 +166,6 @@ void ImageKnob::setRange(float min, float max) noexcept
         }
     }
 
-    if (fValueDef < min)
-        fValueDef = min;
-    else if (fValueDef > max)
-        fValueDef = max;
-
     fMinimum = min;
     fMaximum = max;
 }
@@ -313,7 +312,7 @@ bool ImageKnob::onMouse(const MouseEvent& ev)
         if (! contains(ev.pos))
             return false;
 
-        if (ev.mod & MODIFIER_SHIFT)
+        if ((ev.mod & MODIFIER_SHIFT) != 0 && fUsingDefault)
         {
             setValue(fValueDef);
             fValueTmp = fValue;
diff --git a/distrho/src/DistrhoPlugin.cpp b/distrho/src/DistrhoPlugin.cpp
index 7e9f382c..f1b079b9 100644
--- a/distrho/src/DistrhoPlugin.cpp
+++ b/distrho/src/DistrhoPlugin.cpp
@@ -80,6 +80,9 @@ double Plugin::d_getSampleRate() const noexcept
 #if DISTRHO_PLUGIN_WANT_TIMEPOS
 const TimePos& Plugin::d_getTimePos() const noexcept
 {
+    // timePos outside run() may not be valid
+    DISTRHO_SAFE_ASSERT(pData->isProcessing);
+
     return pData->timePos;
 }
 #endif
diff --git a/distrho/src/DistrhoPluginInternal.hpp b/distrho/src/DistrhoPluginInternal.hpp
index 608a479c..a604c239 100644
--- a/distrho/src/DistrhoPluginInternal.hpp
+++ b/distrho/src/DistrhoPluginInternal.hpp
@@ -36,6 +36,8 @@ extern double   d_lastSampleRate;
 // Plugin private data
 
 struct Plugin::PrivateData {
+    bool isProcessing;
+
     uint32_t   parameterCount;
     Parameter* parameters;
 
@@ -61,7 +63,8 @@ struct Plugin::PrivateData {
     double   sampleRate;
 
     PrivateData() noexcept
-        : parameterCount(0),
+        : isProcessing(false),
+          parameterCount(0),
           parameters(nullptr),
 #if DISTRHO_PLUGIN_WANT_PROGRAMS
           programCount(0),
@@ -353,18 +356,25 @@ public:
 #if DISTRHO_PLUGIN_IS_SYNTH
     void run(const float** const inputs, float** const outputs, const uint32_t frames, const MidiEvent* const midiEvents, const uint32_t midiEventCount)
     {
+        DISTRHO_SAFE_ASSERT_RETURN(fData != nullptr,);
         DISTRHO_SAFE_ASSERT_RETURN(fPlugin != nullptr,);
 
+        fData->isProcessing = true;
         fPlugin->d_run(inputs, outputs, frames, midiEvents, midiEventCount);
+        fData->isProcessing = false;
     }
 #else
     void run(const float** const inputs, float** const outputs, const uint32_t frames)
     {
+        DISTRHO_SAFE_ASSERT_RETURN(fData != nullptr,);
         DISTRHO_SAFE_ASSERT_RETURN(fPlugin != nullptr,);
 
+        fData->isProcessing = true;
         fPlugin->d_run(inputs, outputs, frames);
+        fData->isProcessing = false;
     }
 #endif
+
     // -------------------------------------------------------------------
 
     void setBufferSize(const uint32_t bufferSize, bool doCallback = false)