diff --git a/aspectratio.h b/aspectratio.h
index d3f835e..d393dec 100644
--- a/aspectratio.h
+++ b/aspectratio.h
@@ -41,7 +41,7 @@ inline AspectRatio::AspectRatio(uint16 numerator, uint16 denominator) :
  */
 inline bool AspectRatio::isValid() const
 {
-    return !type || !numerator || !denominator;
+    return type && numerator && denominator;
 }
 
 /*!
diff --git a/matroska/matroskacontainer.cpp b/matroska/matroskacontainer.cpp
index 7668f39..b3277a9 100644
--- a/matroska/matroskacontainer.cpp
+++ b/matroska/matroskacontainer.cpp
@@ -10,9 +10,7 @@
 #include "../backuphelper.h"
 
 // include configuration from separate header file when building with CMake
-#ifndef APP_METADATA_AVAIL
 #include "resources/config.h"
-#endif
 
 #include <c++utilities/conversion/stringconversion.h>
 #include <c++utilities/misc/memory.h>
@@ -58,9 +56,6 @@ MatroskaContainer::MatroskaContainer(MediaFileInfo &fileInfo, uint64 startOffset
     m_doctypeReadVersion = 1;
 }
 
-/*!
- * \brief Destroys the container.
- */
 MatroskaContainer::~MatroskaContainer()
 {}
 
diff --git a/mp4/mp4container.cpp b/mp4/mp4container.cpp
index dbf8b79..2da0322 100644
--- a/mp4/mp4container.cpp
+++ b/mp4/mp4container.cpp
@@ -34,9 +34,6 @@ Mp4Container::Mp4Container(MediaFileInfo &fileInfo, uint64 startOffset) :
     m_fragmented(false)
 {}
 
-/*!
- * \brief Destroys the container.
- */
 Mp4Container::~Mp4Container()
 {}
 
diff --git a/ogg/oggcontainer.cpp b/ogg/oggcontainer.cpp
index 71fb110..ae5b6e7 100644
--- a/ogg/oggcontainer.cpp
+++ b/ogg/oggcontainer.cpp
@@ -20,7 +20,7 @@ namespace Media {
  * \brief Constructs a new container for the specified \a stream at the specified \a startOffset.
  */
 OggContainer::OggContainer(MediaFileInfo &fileInfo, uint64 startOffset) :
-    GenericContainer<MediaFileInfo, VorbisComment, OggStream, OggPage>(fileInfo, startOffset),//AbstractContainer(stream, startOffset)
+    GenericContainer<MediaFileInfo, VorbisComment, OggStream, OggPage>(fileInfo, startOffset),
     m_iterator(fileInfo.stream(), startOffset, fileInfo.size()),
     m_validateChecksums(false)
 {}