diff --git a/ext/mplex/ac3strm_in.cc b/ext/mplex/ac3strm_in.cc
index 5dfc22d181..9c3716ec44 100644
--- a/ext/mplex/ac3strm_in.cc
+++ b/ext/mplex/ac3strm_in.cc
@@ -27,6 +27,7 @@
 
 #include "audiostrm.hh"
 #include "outputstream.hh"
+#include <cassert>
 
 
 
diff --git a/ext/mplex/gstmplex.cc b/ext/mplex/gstmplex.cc
index 1142dd78d5..03cc6e8d2a 100644
--- a/ext/mplex/gstmplex.cc
+++ b/ext/mplex/gstmplex.cc
@@ -87,7 +87,7 @@ GST_PAD_TEMPLATE_FACTORY (audio_sink_factory,
   GST_CAPS_NEW (
     "sink_audio",
     "audio/mpeg",
-      "layer", GST_PROPS_RANGE (1, 3)
+      "layer", GST_PROPS_INT_RANGE (1, 3)
   )
 )
 
diff --git a/ext/mplex/lpcmstrm_in.cc b/ext/mplex/lpcmstrm_in.cc
index 2e73a625ce..448094ed1b 100644
--- a/ext/mplex/lpcmstrm_in.cc
+++ b/ext/mplex/lpcmstrm_in.cc
@@ -28,6 +28,7 @@
 
 #include "audiostrm.hh"
 #include "outputstream.hh"
+#include <cassert>
 
 
 
diff --git a/ext/mplex/multplex.cc b/ext/mplex/multplex.cc
index 5a1d4b1bd5..dcdc97badc 100644
--- a/ext/mplex/multplex.cc
+++ b/ext/mplex/multplex.cc
@@ -10,6 +10,7 @@
 
 #include "videostrm.hh"
 #include "outputstream.hh"
+#include <cassert>
 
 
 /******************************************************************* 
diff --git a/ext/mplex/stillsstream.cc b/ext/mplex/stillsstream.cc
index 95c895052f..1b6d10b382 100644
--- a/ext/mplex/stillsstream.cc
+++ b/ext/mplex/stillsstream.cc
@@ -25,6 +25,7 @@
 
 #include "stillsstream.hh"
 #include "outputstream.hh"
+#include <cassert>
 
 void
 StillsStream::Init ()
diff --git a/ext/mplex/systems.cc b/ext/mplex/systems.cc
index 8aa393790c..fd5b908253 100644
--- a/ext/mplex/systems.cc
+++ b/ext/mplex/systems.cc
@@ -6,6 +6,7 @@
 #include <sys/stat.h>
 #include "systems.hh"
 #include "mplexconsts.hh"
+#include <cassert>
 
 uint8_t dummy_buf[8000];
 void