diff --git a/README.md b/README.md
index 2985922..f62ae10 100644
--- a/README.md
+++ b/README.md
@@ -61,4 +61,4 @@ Unix packages:
 ### Dependencies
 
  * wxWidgets >= 2.8
- * FFmpeg >= 0.7 or libav >= 0.8
+ * A recent version of FFmpeg or libav
diff --git a/configure.ac b/configure.ac
index cd840ae..3979c7e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -6,7 +6,7 @@ AM_SILENT_RULES([yes])
 
 AC_LANG([C++])
 AC_PROG_CXX([clang++ g++])
-CXXFLAGS="$CXXFLAGS -std=gnu++11"
+CXXFLAGS="$CXXFLAGS -std=c++11"
 AC_PROG_CXXCPP
 AC_PROG_RANLIB
 AC_PROG_INSTALL
diff --git a/dist/win/README.md b/dist/win/README.md
index d16a548..0e1a806 100644
--- a/dist/win/README.md
+++ b/dist/win/README.md
@@ -6,8 +6,7 @@ This is done in two steps:
  * Building the MSI package under Windows.
 
 For the first step you can use any Unix-y environment. Set up
-[MXE](http://mxe.cc/#tutorial), you can use the code from
-[this repository](https://github.com/alexkay/mxe/tree/spek) or the official one.
+[MXE](http://mxe.cc/#tutorial).
 
 Build Spek dependencies:
 
diff --git a/src/spek-audio.cc b/src/spek-audio.cc
index 6bced25..7be6224 100644
--- a/src/spek-audio.cc
+++ b/src/spek-audio.cc
@@ -235,7 +235,7 @@ void spek_audio_close(struct spek_audio_context *cx)
         av_free_packet(&cx->packet);
     }
     if (cx->properties.buffer) {
-        av_free(cx->properties.buffer);
+        av_freep(&cx->properties.buffer);
     }
     if (cx->codec_context != NULL) {
         avcodec_close(cx->codec_context);