diff --git a/CMakeLists.txt b/CMakeLists.txt
index ae30f7ad..6294f5fd 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -89,9 +89,9 @@ endif()
 # 2. If any interfaces have been added, removed, or changed since the last update, increment current, and set revision to 0.
 # 3. If any interfaces have been added since the last public release, then increment age.
 # 4. If any interfaces have been removed since the last public release, then set age to 0.
-set(TAGLIB_SOVERSION_CURRENT  16)
-set(TAGLIB_SOVERSION_REVISION 1)
-set(TAGLIB_SOVERSION_AGE      15)
+set(TAGLIB_SOVERSION_CURRENT  17)
+set(TAGLIB_SOVERSION_REVISION 0)
+set(TAGLIB_SOVERSION_AGE      16)
 
 math(EXPR TAGLIB_SOVERSION_MAJOR "${TAGLIB_SOVERSION_CURRENT} - ${TAGLIB_SOVERSION_AGE}")
 math(EXPR TAGLIB_SOVERSION_MINOR "${TAGLIB_SOVERSION_AGE}")
diff --git a/NEWS b/NEWS
index a3e5c93a..787f2d3b 100644
--- a/NEWS
+++ b/NEWS
@@ -1,5 +1,12 @@
+TagLib 1.11 (Jan 30, 2016)
 ==========================
 
+ * Better handling of PCM WAV files with a 'fact' chunk.
+ * Better handling of corrupted APE tags.
+ * Several smaller bug fixes and performance improvements.
+
+1.11 BETA:
+
  * New API for creating FileRef from IOStream.
  * Added support for ID3v2 PCST and WFED frames.
  * Added support for pictures in XiphComment.
@@ -8,6 +15,7 @@
  * Added alternative functions to XiphComment::removeField().
  * Added BUILD_BINDINGS build option.
  * Added ENABLE_CCACHE build option.
+ * Replaced ENABLE_STATIC build option with BUILD_SHARED_LIBS.
  * Better handling of duplicate ID3v2 tags in all kinds of files.
  * Better handling of duplicate tag chunks in WAV files.
  * Better handling of duplicate tag chunks in AIFF files.
@@ -25,10 +33,10 @@
  * Fixed possible file corruptions when saving WavPack files.
  * Fixed updating the comment field of Vorbis comments.
  * Fixed reading date and time in ID3v2.3 tags.
- * Replaced ENABLE_STATIC build option with BUILD_SHARED_LIBS.
  * Marked ByteVector::null and ByteVector::isNull() deprecated.
  * Marked String::null and ByteVector::isNull() deprecated.
  * Marked XiphComment::removeField() deprecated.
+ * Marked Ogg::Page::getCopyWithNewPageSequenceNumber() deprecated. It returns null.
  * Marked custom integer types deprecated.
  * Many smaller bug fixes and performance improvements.
 
diff --git a/taglib/ape/apeitem.cpp b/taglib/ape/apeitem.cpp
index 35236eca..661d2412 100644
--- a/taglib/ape/apeitem.cpp
+++ b/taglib/ape/apeitem.cpp
@@ -34,7 +34,9 @@ using namespace APE;
 class APE::Item::ItemPrivate
 {
 public:
-  ItemPrivate() : type(Text), readOnly(false) {}
+  ItemPrivate() :
+    type(Text),
+    readOnly(false) {}
 
   Item::ItemTypes type;
   String key;
@@ -74,8 +76,9 @@ APE::Item::Item(const String &key, const ByteVector &value, bool binary) :
     d->type = Binary;
     d->value = value;
   }
-  else
+  else {
     d->text.append(value);
+  }
 }
 
 APE::Item::Item(const Item &item) :
@@ -173,9 +176,8 @@ void APE::Item::appendValues(const StringList &values)
 
 int APE::Item::size() const
 {
-  // SFB: Why is d->key.size() used when size() returns the length in UniChars and not UTF-8?
-  size_t result = 8 + d->key.size() /* d->key.data(String::UTF8).size() */ + 1;
-  switch (d->type) {
+  size_t result = 8 + d->key.size() + 1;
+  switch(d->type) {
     case Text:
       if(!d->text.isEmpty()) {
         StringList::ConstIterator it = d->text.begin();
@@ -237,7 +239,10 @@ void APE::Item::parse(const ByteVector &data)
   const unsigned int valueLength  = data.toUInt32LE(0);
   const unsigned int flags        = data.toUInt32LE(4);
 
-  d->key = String(data.mid(8), String::UTF8);
+  // An item key can contain ASCII characters from 0x20 up to 0x7E, not UTF-8.
+  // We assume that the validity of the given key has been checked.
+
+  d->key = String(&data[8], String::Latin1);
 
   const ByteVector value = data.mid(8 + d->key.size() + 1, valueLength);
 
@@ -275,7 +280,7 @@ ByteVector APE::Item::render() const
 
   data.append(ByteVector::fromUInt32LE(value.size()));
   data.append(ByteVector::fromUInt32LE(flags));
-  data.append(d->key.data(String::UTF8));
+  data.append(d->key.data(String::Latin1));
   data.append(ByteVector('\0'));
   data.append(value);
 
diff --git a/taglib/ape/apetag.cpp b/taglib/ape/apetag.cpp
index 4d592bb4..a8c181bf 100644
--- a/taglib/ape/apetag.cpp
+++ b/taglib/ape/apetag.cpp
@@ -36,6 +36,8 @@
 #include <tmap.h>
 #include <tpicturemap.h>
 #include <tpropertymap.h>
+#include <tdebug.h>
+#include <tutils.h>
 
 #include "apetag.h"
 #include "apefooter.h"
@@ -44,6 +46,32 @@
 using namespace TagLib;
 using namespace APE;
 
+namespace
+{
+  inline bool isKeyValid(const char *key, size_t length)
+  {
+    const char *invalidKeys[] = { "ID3", "TAG", "OGGS", "MP+", 0 };
+
+    if(length < 2 || length > 16)
+      return false;
+
+    // only allow printable ASCII including space (32..126)
+
+    for(const char *p = key; p < key + length; ++p) {
+      const int c = static_cast<unsigned char>(*p);
+      if(c < 32 || c > 126)
+        return false;
+    }
+
+    for(size_t i = 0; invalidKeys[i] != 0; ++i) {
+      if(Utils::equalsIgnoreCase(key, invalidKeys[i]))
+        return false;
+    }
+
+    return true;
+  }
+}
+
 class APE::Tag::TagPrivate
 {
 public:
@@ -362,16 +390,11 @@ PropertyMap APE::Tag::setProperties(const PropertyMap &origProps)
 
 bool APE::Tag::checkKey(const String &key)
 {
-  if(key.size() < 2 || key.size() > 16)
-      return false;
-    for(String::ConstIterator it = key.begin(); it != key.end(); it++)
-        // only allow printable ASCII including space (32..127)
-        if (*it < 32 || *it >= 128)
-          return false;
-    String upperKey = key.upper();
-    if (upperKey=="ID3" || upperKey=="TAG" || upperKey=="OGGS" || upperKey=="MP+")
-      return false;
-    return true;
+  if(!key.isLatin1())
+    return false;
+
+  const std::string data = key.to8Bit(false);
+  return isKeyValid(data.c_str(), data.size());
 }
 
 APE::Footer *APE::Tag::footer() const
@@ -393,31 +416,39 @@ void APE::Tag::addValue(const String &key, const String &value, bool replace)
 {
   if(replace)
     removeItem(key);
-  if(!key.isEmpty() && !value.isEmpty()) {
-    if(!replace && d->itemListMap.contains(key)) {
-      // Text items may contain more than one value
-      if(APE::Item::Text == d->itemListMap.begin()->second.type())
-        d->itemListMap[key.upper()].appendValue(value);
-      // Binary or locator items may have only one value
-      else
-        setItem(key, Item(key, value));
-    }
-    else
-      setItem(key, Item(key, value));
-  }
+
+  if(value.isEmpty())
+    return;
+
+  // Text items may contain more than one value.
+  // Binary or locator items may have only one value, hence always replaced.
+
+  ItemListMap::Iterator it = d->itemListMap.find(key.upper());
+
+  if(it != d->itemListMap.end() && it->second.type() == Item::Text)
+    it->second.appendValue(value);
+  else
+    setItem(key, Item(key, value));
 }
 
 void APE::Tag::setData(const String &key, const ByteVector &value)
 {
   removeItem(key);
-  if(!key.isEmpty() && !value.isEmpty())
-    setItem(key, Item(key, value, true));
+
+  if(value.isEmpty())
+    return;
+
+  setItem(key, Item(key, value, true));
 }
 
 void APE::Tag::setItem(const String &key, const Item &item)
 {
-  if(!key.isEmpty())
-    d->itemListMap.insert(key.upper(), item);
+  if(!checkKey(key)) {
+    debug("APE::Tag::setItem() - Couldn't set an item due to an invalid key.");
+    return;
+  }
+
+  d->itemListMap[key.upper()] = item;
 }
 
 bool APE::Tag::isEmpty() const
@@ -469,14 +500,29 @@ void APE::Tag::parse(const ByteVector &data)
   if(data.size() < 11)
     return;
 
-  unsigned int pos = 0;
+  size_t pos = 0;
 
   for(unsigned int i = 0; i < d->footer.itemCount() && pos <= data.size() - 11; i++) {
-    APE::Item item;
-    item.parse(data.mid(pos));
 
-    d->itemListMap.insert(item.key().upper(), item);
+    const size_t nullPos = data.find('\0', pos + 8);
+    if(nullPos == ByteVector::npos()) {
+      debug("APE::Tag::parse() - Couldn't find a key/value separator. Stopped parsing.");
+      return;
+    }
 
-    pos += item.size();
+    const size_t keyLength = nullPos - pos - 8;
+    const size_t valLegnth = data.toUInt32LE(pos);
+
+    if(isKeyValid(&data[pos + 8], keyLength)){
+      APE::Item item;
+      item.parse(data.mid(pos));
+
+      d->itemListMap.insert(item.key().upper(), item);
+    }
+    else {
+      debug("APE::Tag::parse() - Skipped an item due to an invalid key.");
+    }
+
+    pos += keyLength + valLegnth + 9;
   }
 }
diff --git a/taglib/mpeg/mpegheader.cpp b/taglib/mpeg/mpegheader.cpp
index e6c210ec..d2e528c7 100644
--- a/taglib/mpeg/mpegheader.cpp
+++ b/taglib/mpeg/mpegheader.cpp
@@ -299,27 +299,30 @@ void MPEG::Header::parse(File *file, long long offset, bool checkLength)
   if(d->data->isPadded)
     d->data->frameLength += paddingSize[layerIndex];
 
-  // Check if the frame length has been calculated correctly, or the next frame
-  // synch bytes are right next to the end of this frame.
-
-  // We read some extra bytes to be a bit tolerant.
-
   if(checkLength) {
 
-    bool nextFrameFound = false;
+    // Check if the frame length has been calculated correctly, or the next frame
+    // header is right next to the end of this frame.
+
+    // The MPEG versions, layers and sample rates of the two frames should be
+    // consistent. Otherwise, we assume that either or both of the frames are
+    // broken.
 
     file->seek(offset + d->data->frameLength);
-    const ByteVector nextSynch = file->readBlock(4);
+    const ByteVector nextData = file->readBlock(4);
 
-    for(int i = 0; i < static_cast<int>(nextSynch.size()) - 1; ++i) {
-      if(firstSyncByte(nextSynch[i]) && secondSynchByte(nextSynch[i + 1])) {
-        nextFrameFound = true;
-        break;
-      }
+    if(nextData.size() < 4) {
+      debug("MPEG::Header::parse() -- Could not read the next frame header.");
+      return;
     }
 
-    if(!nextFrameFound) {
-      debug("MPEG::Header::parse() -- Calculated frame length did not match the actual length.");
+    const unsigned int HeaderMask = 0xfffe0c00;
+
+    const unsigned int header     = data.toUInt32BE(0)     & HeaderMask;
+    const unsigned int nextHeader = nextData.toUInt32BE(0) & HeaderMask;
+
+    if(header != nextHeader) {
+      debug("MPEG::Header::parse() -- The next frame was not consistent with this frame.");
       return;
     }
   }
diff --git a/taglib/mpeg/mpegutils.h b/taglib/mpeg/mpegutils.h
index 78cee280..5a7e0e6a 100644
--- a/taglib/mpeg/mpegutils.h
+++ b/taglib/mpeg/mpegutils.h
@@ -48,7 +48,9 @@ namespace TagLib
 
     inline bool secondSynchByte(unsigned char byte)
     {
-      return ((byte & 0xE0) == 0xE0);
+      // 0xFF is possible in theory, but it's very unlikely be a header.
+
+      return (byte != 0xFF && ((byte & 0xE0) == 0xE0));
     }
 
   }
diff --git a/taglib/ogg/oggpage.cpp b/taglib/ogg/oggpage.cpp
index 2bf7fa5e..911cc7ca 100644
--- a/taglib/ogg/oggpage.cpp
+++ b/taglib/ogg/oggpage.cpp
@@ -269,27 +269,10 @@ List<Ogg::Page *> Ogg::Page::paginate(const ByteVectorList &packets,
   return l;
 }
 
-Ogg::Page* Ogg::Page::getCopyWithNewPageSequenceNumber(int sequenceNumber)
+Ogg::Page* Ogg::Page::getCopyWithNewPageSequenceNumber(int /*sequenceNumber*/)
 {
-  Page *pResultPage = NULL;
-
-  // TODO: a copy constructor would be helpful
-
-  if(d->file == 0) {
-    pResultPage = new Page(
-        d->packets,
-        d->header.streamSerialNumber(),
-        sequenceNumber,
-        d->header.firstPacketContinued(),
-        d->header.lastPacketCompleted(),
-        d->header.lastPageOfStream());
-  }
-  else
-  {
-    pResultPage = new Page(d->file, d->fileOffset);
-    pResultPage->d->header.setPageSequenceNumber(sequenceNumber);
-  }
-  return pResultPage;
+  debug("Ogg::Page::getCopyWithNewPageSequenceNumber() -- This function is obsolete. Returning null.");
+  return 0;
 }
 
 ////////////////////////////////////////////////////////////////////////////////
diff --git a/taglib/ogg/oggpage.h b/taglib/ogg/oggpage.h
index cc633180..a8c689b8 100644
--- a/taglib/ogg/oggpage.h
+++ b/taglib/ogg/oggpage.h
@@ -91,7 +91,7 @@ namespace TagLib {
        * \see header()
        * \see PageHeader::setPageSequenceNumber()
        *
-       * \deprecated
+       * \deprecated Always returns null.
        */
       Page* getCopyWithNewPageSequenceNumber(int sequenceNumber);
 
diff --git a/taglib/riff/wav/wavproperties.cpp b/taglib/riff/wav/wavproperties.cpp
index 97d6aea7..4eb1c931 100644
--- a/taglib/riff/wav/wavproperties.cpp
+++ b/taglib/riff/wav/wavproperties.cpp
@@ -180,7 +180,7 @@ void RIFF::WAV::AudioProperties::read(File *file)
   d->sampleRate    = data.toUInt32LE(4);
   d->bitsPerSample = data.toUInt16LE(14);
 
-  if(totalSamples > 0)
+  if(d->format != FORMAT_PCM)
     d->sampleFrames = totalSamples;
   else if(d->channels > 0 && d->bitsPerSample > 0)
     d->sampleFrames = streamLength / (d->channels * ((d->bitsPerSample + 7) / 8));
diff --git a/taglib/toolkit/taglib.h b/taglib/toolkit/taglib.h
index da0d3e35..2f4c5655 100644
--- a/taglib/toolkit/taglib.h
+++ b/taglib/toolkit/taglib.h
@@ -27,7 +27,7 @@
 #define TAGLIB_H
 
 #define TAGLIB_MAJOR_VERSION 1
-#define TAGLIB_MINOR_VERSION 10
+#define TAGLIB_MINOR_VERSION 11
 #define TAGLIB_PATCH_VERSION 0
 
 #if (defined(_MSC_VER) && _MSC_VER >= 1600)
diff --git a/taglib/toolkit/tutils.h b/taglib/toolkit/tutils.h
index 3d2c5488..d7adee29 100644
--- a/taglib/toolkit/tutils.h
+++ b/taglib/toolkit/tutils.h
@@ -219,6 +219,23 @@ namespace TagLib
         return String();
     }
 
+    /*!
+     * Returns whether the two strings s1 and s2 are equal, ignoring the case of
+     * the characters.
+     *
+     * We took the trouble to define this one here, since there are some
+     * incompatible variations of case insensitive strcmp().
+     */
+    inline bool equalsIgnoreCase(const char *s1, const char *s2)
+    {
+      while(*s1 != '\0' && *s2 != '\0' && ::tolower(*s1) == ::tolower(*s2)) {
+        s1++;
+        s2++;
+      }
+
+      return (*s1 == '\0' && *s2 == '\0');
+    }
+
     /*!
      * Returns the integer byte order of the system.
      */
diff --git a/tests/data/invalid-frames.mp3 b/tests/data/invalid-frames1.mp3
similarity index 100%
rename from tests/data/invalid-frames.mp3
rename to tests/data/invalid-frames1.mp3
diff --git a/tests/data/invalid-frames3.mp3 b/tests/data/invalid-frames3.mp3
new file mode 100644
index 00000000..6bbd2d39
Binary files /dev/null and b/tests/data/invalid-frames3.mp3 differ
diff --git a/tests/data/pcm_with_fact_chunk.wav b/tests/data/pcm_with_fact_chunk.wav
new file mode 100644
index 00000000..a6dc1d6c
Binary files /dev/null and b/tests/data/pcm_with_fact_chunk.wav differ
diff --git a/tests/test_apetag.cpp b/tests/test_apetag.cpp
index 81bfe8cf..e3391821 100644
--- a/tests/test_apetag.cpp
+++ b/tests/test_apetag.cpp
@@ -97,6 +97,11 @@ public:
     CPPUNIT_ASSERT_EQUAL((size_t)2, unsuccessful.size());
     CPPUNIT_ASSERT(unsuccessful.contains("A"));
     CPPUNIT_ASSERT(unsuccessful.contains("MP+"));
+
+    CPPUNIT_ASSERT_EQUAL((unsigned int)2, tag.itemListMap().size());
+    tag.addValue("VALID KEY", "Test Value 1");
+    tag.addValue("INVALID KEY \x7f", "Test Value 2");
+    CPPUNIT_ASSERT_EQUAL((unsigned int)3, tag.itemListMap().size());
   }
 
   void testTextBinary()
diff --git a/tests/test_mpeg.cpp b/tests/test_mpeg.cpp
index 5b58efcb..72398146 100644
--- a/tests/test_mpeg.cpp
+++ b/tests/test_mpeg.cpp
@@ -24,6 +24,7 @@ class TestMPEG : public CppUnit::TestFixture
   CPPUNIT_TEST(testAudioPropertiesNoVBRHeaders);
   CPPUNIT_TEST(testSkipInvalidFrames1);
   CPPUNIT_TEST(testSkipInvalidFrames2);
+  CPPUNIT_TEST(testSkipInvalidFrames3);
   CPPUNIT_TEST(testVersion2DurationWithXingHeader);
   CPPUNIT_TEST(testSaveID3v24);
   CPPUNIT_TEST(testSaveID3v24WrongParam);
@@ -107,7 +108,7 @@ public:
 
   void testSkipInvalidFrames1()
   {
-    MPEG::File f(TEST_FILE_PATH_C("invalid-frames.mp3"));
+    MPEG::File f(TEST_FILE_PATH_C("invalid-frames1.mp3"));
     CPPUNIT_ASSERT(f.audioProperties());
     CPPUNIT_ASSERT_EQUAL(0, f.audioProperties()->length());
     CPPUNIT_ASSERT_EQUAL(0, f.audioProperties()->lengthInSeconds());
@@ -131,6 +132,19 @@ public:
     CPPUNIT_ASSERT(!f.audioProperties()->xingHeader());
   }
 
+  void testSkipInvalidFrames3()
+  {
+    MPEG::File f(TEST_FILE_PATH_C("invalid-frames3.mp3"));
+    CPPUNIT_ASSERT(f.audioProperties());
+    CPPUNIT_ASSERT_EQUAL(0, f.audioProperties()->length());
+    CPPUNIT_ASSERT_EQUAL(0, f.audioProperties()->lengthInSeconds());
+    CPPUNIT_ASSERT_EQUAL(176, f.audioProperties()->lengthInMilliseconds());
+    CPPUNIT_ASSERT_EQUAL(320, f.audioProperties()->bitrate());
+    CPPUNIT_ASSERT_EQUAL(2, f.audioProperties()->channels());
+    CPPUNIT_ASSERT_EQUAL(44100, f.audioProperties()->sampleRate());
+    CPPUNIT_ASSERT(!f.audioProperties()->xingHeader());
+  }
+
   void testVersion2DurationWithXingHeader()
   {
     MPEG::File f(TEST_FILE_PATH_C("mpeg2.mp3"));
diff --git a/tests/test_wav.cpp b/tests/test_wav.cpp
index 96891877..ade4f3f7 100644
--- a/tests/test_wav.cpp
+++ b/tests/test_wav.cpp
@@ -25,6 +25,7 @@ class TestWAV : public CppUnit::TestFixture
   CPPUNIT_TEST(testFuzzedFile1);
   CPPUNIT_TEST(testFuzzedFile2);
   CPPUNIT_TEST(testStripAndProperties);
+  CPPUNIT_TEST(testPCMWithFactChunk);
   CPPUNIT_TEST_SUITE_END();
 
 public:
@@ -247,6 +248,22 @@ public:
     }
   }
 
+  void testPCMWithFactChunk()
+  {
+    RIFF::WAV::File f(TEST_FILE_PATH_C("pcm_with_fact_chunk.wav"));
+    CPPUNIT_ASSERT(f.audioProperties());
+    CPPUNIT_ASSERT_EQUAL(3, f.audioProperties()->length());
+    CPPUNIT_ASSERT_EQUAL(3, f.audioProperties()->lengthInSeconds());
+    CPPUNIT_ASSERT_EQUAL(3675, f.audioProperties()->lengthInMilliseconds());
+    CPPUNIT_ASSERT_EQUAL(32, f.audioProperties()->bitrate());
+    CPPUNIT_ASSERT_EQUAL(2, f.audioProperties()->channels());
+    CPPUNIT_ASSERT_EQUAL(1000, f.audioProperties()->sampleRate());
+    CPPUNIT_ASSERT_EQUAL(16, f.audioProperties()->bitsPerSample());
+    CPPUNIT_ASSERT_EQUAL(16, f.audioProperties()->sampleWidth());
+    CPPUNIT_ASSERT_EQUAL(3675U, f.audioProperties()->sampleFrames());
+    CPPUNIT_ASSERT_EQUAL(1, f.audioProperties()->format());
+  }
+
 };
 
 CPPUNIT_TEST_SUITE_REGISTRATION(TestWAV);