diff --git a/vocto/transitions.py b/vocto/transitions.py
index 22197e45..b6d763b1 100644
--- a/vocto/transitions.py
+++ b/vocto/transitions.py
@@ -183,7 +183,7 @@ def hidden( x, hidden ):
         result = "\t%s = %s -> %s:\n" % (self.name(),
                                       self.begin().name, self.end().name)
         # add table title
-        result += "\tNo. %s\n" % Composite.str_title()
+        result += "\tNo. %s\n" % Composite.str_title(self)
         # add composites until flipping point
         for i in range(self.frames()):
             if (not logKeyFramesOnly) or self.A(i).key:
diff --git a/voctocore/lib/videomix.py b/voctocore/lib/videomix.py
index 85539442..d18426c3 100644
--- a/voctocore/lib/videomix.py
+++ b/voctocore/lib/videomix.py
@@ -90,7 +90,7 @@ def __init__(self):
         for idx, name in enumerate(self.sources):
             self.bin += """
                 video-{name}.
-                ! queue
+                ! videobox
                     name=cropper-{name}
                 ! queue
                     max-size-time=3000000000
@@ -114,7 +114,7 @@ def attach(self, pipeline):
         self.log.debug('Initializing Mixer-State')
         # initialize pipeline bindings for all sources
         self.bgScene = Scene(self.bgSources, pipeline, self.transitions.fps, 0, cropping=False)
-        self.scene = Scene(self.sources, pipeline, self.transitions.fps, len(self.bgSources), cropping=False)
+        self.scene = Scene(self.sources, pipeline, self.transitions.fps, len(self.bgSources))
         self.compositeMode = None
         self.sourceA = None
         self.sourceB = None