diff --git a/Mixer.cpp b/Mixer.cpp
index ab1993f..ac00b52 100644
--- a/Mixer.cpp
+++ b/Mixer.cpp
@@ -668,8 +668,9 @@ void Mixer::groupSelection()
     // set depth at given location
     group->group(View::LAYER)->translation_.z = d;
 
-    // scale alpha
-    group->setAlpha( 1.f );
+    // set alpha to full opacity
+    group->group(View::MIXING)->translation_.x = 0.f;
+    group->group(View::MIXING)->translation_.y = 0.f;
 
     // Add source to Session
     session_->addSource(group);
diff --git a/Session.cpp b/Session.cpp
index afe36fd..556d474 100644
--- a/Session.cpp
+++ b/Session.cpp
@@ -74,10 +74,8 @@ void Session::update(float dt)
 
         // ensure the RenderSource is rendering this session
         RenderSource *s = dynamic_cast<RenderSource *>( *it );
-        if ( s!= nullptr ){
-            if ( s->session() != this /*|| s->session()->frame()->resolution() != frame()->resolution()*/)
-                s->setSession(nullptr); // RenderSource will fail and be replaced
-        }
+        if ( s!= nullptr && s->session() != this )
+                s->setSession(this);
 
         if ( (*it)->failed() ) {
             failedSource_ = (*it);
@@ -198,8 +196,10 @@ Source *Session::popSource()
 
 void Session::setResolution(glm::vec3 resolution, bool useAlpha)
 {
+    // setup the render view: if not specified the default config resulution will be used
     render_.setResolution( resolution, useAlpha );
-    config_[View::RENDERING]->scale_ = resolution;
+    // store the actual resolution set in the render view
+    config_[View::RENDERING]->scale_ = render_.resolution();
 }
 
 void Session::setFading(float f, bool forcenow)
diff --git a/SessionSource.cpp b/SessionSource.cpp
index 3a1dd74..4a7da94 100644
--- a/SessionSource.cpp
+++ b/SessionSource.cpp
@@ -329,7 +329,10 @@ RenderSource::RenderSource() : Source(), session_(nullptr)
 
 bool RenderSource::failed() const
 {
-    return (initialized_ && session_ == nullptr);
+    if (initialized_ && session_!=nullptr)
+        return renderbuffer_->resolution() != session_->frame()->resolution();
+
+    return false;
 }
 
 uint RenderSource::texture() const
@@ -365,6 +368,16 @@ void RenderSource::init()
 }
 
 
+glm::vec3 RenderSource::resolution() const
+{
+    if (initialized_)
+        return renderbuffer_->resolution();
+    else if (session_ && session_->frame())
+        return session_->frame()->resolution();
+    else
+        return glm::vec3(0.f);
+}
+
 void RenderSource::accept(Visitor& v)
 {
     Source::accept(v);
diff --git a/SessionSource.h b/SessionSource.h
index c51b2b1..9cce888 100644
--- a/SessionSource.h
+++ b/SessionSource.h
@@ -89,6 +89,8 @@ public:
     inline Session *session () const { return session_; }
     inline void setSession (Session *se) { session_ = se; }
 
+    glm::vec3 resolution() const;
+
     glm::ivec2 icon() const override { return glm::ivec2(0, 2); }
 
 protected: