diff --git a/HISTORY b/HISTORY
index 8ad877e..af164c1 100644
--- a/HISTORY
+++ b/HISTORY
@@ -525,3 +525,12 @@ VDR Plugin 'femon' Revision History
 - Got rid of FEMON_DEBUG.
 - Added support for tracing modes.
 - Removed the 'femonclient' plugin.
+
+
+===================================
+VDR Plugin 'femon' Revision History
+===================================
+
+2015-XX-XX: Version 2.3.0
+
+- Updated for vdr-2.3.1.
diff --git a/femon.c b/femon.c
index 91b4846..faa9d20 100644
--- a/femon.c
+++ b/femon.c
@@ -17,15 +17,15 @@
 #include "tools.h"
 #include "setup.h"
 
-#if defined(APIVERSNUM) && APIVERSNUM < 20200
-#error "VDR-2.2.0 API version or greater is required!"
+#if defined(APIVERSNUM) && APIVERSNUM < 20301
+#error "VDR-2.3.1 API version or greater is required!"
 #endif
 
 #ifndef GITVERSION
 #define GITVERSION ""
 #endif
 
-static const char VERSION[]       = "2.2.1" GITVERSION;
+static const char VERSION[]       = "2.3.0" GITVERSION;
 static const char DESCRIPTION[]   = trNOOP("DVB Signal Information Monitor (OSD)");
 static const char MAINMENUENTRY[] = trNOOP("Signal Information");
 
@@ -120,7 +120,8 @@ cOsdObject *cPluginFemon::MainMenuAction(void)
 {
   // Perform the action when selected from the main VDR menu.
   debug1("%s", __PRETTY_FUNCTION__);
-  if (cControl::Control() || (Channels.Count() <= 0))
+  LOCK_CHANNELS_READ;
+  if (cControl::Control() || (Channels->Count() <= 0))
      Skins.Message(mtInfo, tr("Femon not available"));
   else
      return cFemonOsd::Instance(true);
diff --git a/osd.c b/osd.c
index 7158642..f6baaac 100644
--- a/osd.c
+++ b/osd.c
@@ -250,7 +250,8 @@ cFemonOsd::~cFemonOsd(void)
 void cFemonOsd::DrawStatusWindow(void)
 {
   cMutexLock lock(&mutexM);
-  cChannel *channel = Channels.GetByNumber(cDevice::CurrentChannel());
+  LOCK_CHANNELS_READ;
+  const cChannel *channel = Channels->GetByNumber(cDevice::CurrentChannel());
 
   if (osdM && channel) {
      cBitmap *bm = NULL;
@@ -394,7 +395,8 @@ void cFemonOsd::DrawStatusWindow(void)
 void cFemonOsd::DrawInfoWindow(void)
 {
   cMutexLock lock(&mutexM);
-  cChannel *channel = Channels.GetByNumber(cDevice::CurrentChannel());
+  LOCK_CHANNELS_READ;
+  const cChannel *channel = Channels->GetByNumber(cDevice::CurrentChannel());
 
   if (osdM && channel) {
      int offset = 0;
@@ -716,7 +718,8 @@ void cFemonOsd::Show(void)
 {
   debug1("%s", __PRETTY_FUNCTION__);
   eTrackType track = cDevice::PrimaryDevice()->GetCurrentAudioTrack();
-  const cChannel *channel = Channels.GetByNumber(cDevice::CurrentChannel());
+  LOCK_CHANNELS_READ;
+  const cChannel *channel = Channels->GetByNumber(cDevice::CurrentChannel());
 
   deviceSourceM = DEVICESOURCE_DVBAPI;
   if (channel) {
@@ -784,7 +787,8 @@ void cFemonOsd::ChannelSwitch(const cDevice * deviceP, int channelNumberP, bool
 {
   debug1("%s (%d, %d, %d)", __PRETTY_FUNCTION__, deviceP->DeviceNumber(), channelNumberP, liveViewP);
   eTrackType track = cDevice::PrimaryDevice()->GetCurrentAudioTrack();
-  const cChannel *channel = Channels.GetByNumber(cDevice::CurrentChannel());
+  LOCK_CHANNELS_READ;
+  const cChannel *channel = Channels->GetByNumber(cDevice::CurrentChannel());
 
   if (!deviceP || !liveViewP)
      return;
@@ -852,7 +856,8 @@ void cFemonOsd::SetAudioTrack(int indexP, const char * const *tracksP)
      DELETENULL(receiverM);
      }
   if (FemonConfig.GetAnalyzeStream()) {
-     const cChannel *channel = Channels.GetByNumber(cDevice::CurrentChannel());
+     LOCK_CHANNELS_READ;
+     const cChannel *channel = Channels->GetByNumber(cDevice::CurrentChannel());
      if (channel) {
         receiverM = new cFemonReceiver(channel, IS_AUDIO_TRACK(track) ? int(track - ttAudioFirst) : 0, IS_DOLBY_TRACK(track) ? int(track - ttDolbyFirst) : 0);
         cDevice::ActualDevice()->AttachReceiver(receiverM);
@@ -866,7 +871,8 @@ bool cFemonOsd::DeviceSwitch(int directionP)
   int device = cDevice::ActualDevice()->DeviceNumber();
   int direction = sgn(directionP);
   if (device >= 0) {
-     cChannel *channel = Channels.GetByNumber(cDevice::CurrentChannel());
+     LOCK_CHANNELS_READ;
+     const cChannel *channel = Channels->GetByNumber(cDevice::CurrentChannel());
      if (channel) {
         for (int i = 0; i < cDevice::NumDevices() - 1; i++) {
             if (direction >= 0) {
@@ -978,7 +984,8 @@ bool cFemonOsd::SvdrpConnect(void)
 bool cFemonOsd::SvdrpTune(void)
 {
    if (svdrpPluginM && svdrpConnectionM.handle >= 0) {
-      cChannel *channel = Channels.GetByNumber(cDevice::CurrentChannel());
+      LOCK_CHANNELS_READ;
+      const cChannel *channel = Channels->GetByNumber(cDevice::CurrentChannel());
       if (channel) {
          SvdrpCommand_v1_0 cmd;
          cmd.handle = svdrpConnectionM.handle;
@@ -1038,7 +1045,8 @@ eOSState cFemonOsd::ProcessKey(eKeys keyP)
             if ((numberM == 0) && (oldNumberM != 0)) {
                numberM = oldNumberM;
                oldNumberM = cDevice::CurrentChannel();
-               Channels.SwitchTo(numberM);
+               LOCK_CHANNELS_READ;
+               Channels->SwitchTo(numberM);
                numberM = 0;
                return osContinue;
                }
@@ -1047,11 +1055,12 @@ eOSState cFemonOsd::ProcessKey(eKeys keyP)
                numberM = numberM * 10 + keyP - k0;
                if (numberM > 0) {
                   DrawStatusWindow();
-                  cChannel *ch = Channels.GetByNumber(numberM);
+                  LOCK_CHANNELS_READ;
+                  const cChannel *ch = Channels->GetByNumber(numberM);
                   inputTimeM.Set(0);
                   // Lets see if there can be any useful further input:
                   int n = ch ? numberM * 10 : 0;
-                  while (ch && (ch = Channels.Next(ch)) != NULL) {
+                  while (ch && (ch = Channels->Next(ch)) != NULL) {
                         if (!ch->GroupSep()) {
                            if (n <= ch->Number() && ch->Number() <= n + 9) {
                               n = 0;
@@ -1064,7 +1073,7 @@ eOSState cFemonOsd::ProcessKey(eKeys keyP)
                   if (n > 0) {
                      // This channel is the only one that fits the input, so let's take it right away:
                      oldNumberM = cDevice::CurrentChannel();
-                     Channels.SwitchTo(numberM);
+                     Channels->SwitchTo(numberM);
                      numberM = 0;
                      }
                   }
@@ -1124,9 +1133,10 @@ eOSState cFemonOsd::ProcessKey(eKeys keyP)
             break;
        case kNone:
             if (numberM && (inputTimeM.Elapsed() > CHANNELINPUT_TIMEOUT)) {
-               if (Channels.GetByNumber(numberM)) {
+               LOCK_CHANNELS_READ;
+               if (Channels->GetByNumber(numberM)) {
                   oldNumberM = cDevice::CurrentChannel();
-                  Channels.SwitchTo(numberM);
+                  Channels->SwitchTo(numberM);
                   numberM = 0;
                   }
                else {
@@ -1138,7 +1148,8 @@ eOSState cFemonOsd::ProcessKey(eKeys keyP)
        case kOk:
             {
             // toggle between display modes
-            cChannel *channel = Channels.GetByNumber(cDevice::CurrentChannel());
+            LOCK_CHANNELS_READ;
+            const cChannel *channel = Channels->GetByNumber(cDevice::CurrentChannel());
             if (++displayModeM == eFemonModeAC3 && channel && !channel->Dpid(0)) displayModeM++;
             if (displayModeM >= eFemonModeMaxNumber) displayModeM = 0;
             DrawInfoWindow();
diff --git a/po/de_DE.po b/po/de_DE.po
index 5dd2004..92f9e2d 100644
--- a/po/de_DE.po
+++ b/po/de_DE.po
@@ -7,7 +7,7 @@
 #
 msgid ""
 msgstr ""
-"Project-Id-Version: vdr-femon 2.2.1\n"
+"Project-Id-Version: vdr-femon 2.3.0\n"
 "Report-Msgid-Bugs-To: <see README>\n"
 "POT-Creation-Date: 2015-04-04 04:04+0300\n"
 "PO-Revision-Date: 2015-04-04 04:04+0300\n"
diff --git a/po/es_ES.po b/po/es_ES.po
index b93f35f..ce68781 100644
--- a/po/es_ES.po
+++ b/po/es_ES.po
@@ -5,7 +5,7 @@
 #
 msgid ""
 msgstr ""
-"Project-Id-Version: vdr-femon 2.2.1\n"
+"Project-Id-Version: vdr-femon 2.3.0\n"
 "Report-Msgid-Bugs-To: <see README>\n"
 "POT-Creation-Date: 2015-04-04 04:04+0300\n"
 "PO-Revision-Date: 2015-04-04 04:04+0300\n"
diff --git a/po/et_EE.po b/po/et_EE.po
index d114787..fde546c 100644
--- a/po/et_EE.po
+++ b/po/et_EE.po
@@ -5,7 +5,7 @@
 #
 msgid ""
 msgstr ""
-"Project-Id-Version: vdr-femon 2.2.1\n"
+"Project-Id-Version: vdr-femon 2.3.0\n"
 "Report-Msgid-Bugs-To: <see README>\n"
 "POT-Creation-Date: 2015-04-04 04:04+0300\n"
 "PO-Revision-Date: 2015-04-04 04:04+0300\n"
diff --git a/po/fi_FI.po b/po/fi_FI.po
index 9c936b4..0ac7ed1 100644
--- a/po/fi_FI.po
+++ b/po/fi_FI.po
@@ -5,7 +5,7 @@
 #
 msgid ""
 msgstr ""
-"Project-Id-Version: vdr-femon 2.2.1\n"
+"Project-Id-Version: vdr-femon 2.3.0\n"
 "Report-Msgid-Bugs-To: <see README>\n"
 "POT-Creation-Date: 2015-04-04 04:04+0300\n"
 "PO-Revision-Date: 2015-04-04 04:04+0300\n"
diff --git a/po/fr_FR.po b/po/fr_FR.po
index 531fb23..b49a723 100644
--- a/po/fr_FR.po
+++ b/po/fr_FR.po
@@ -7,7 +7,7 @@
 #
 msgid ""
 msgstr ""
-"Project-Id-Version: vdr-femon 2.2.1\n"
+"Project-Id-Version: vdr-femon 2.3.0\n"
 "Report-Msgid-Bugs-To: <see README>\n"
 "POT-Creation-Date: 2015-04-04 04:04+0300\n"
 "PO-Revision-Date: 2015-04-04 04:04+0300\n"
diff --git a/po/hu_HU.po b/po/hu_HU.po
index 88a29ca..f913b41 100644
--- a/po/hu_HU.po
+++ b/po/hu_HU.po
@@ -5,7 +5,7 @@
 #
 msgid ""
 msgstr ""
-"Project-Id-Version: vdr-femon 2.2.1\n"
+"Project-Id-Version: vdr-femon 2.3.0\n"
 "Report-Msgid-Bugs-To: <see README>\n"
 "POT-Creation-Date: 2015-04-04 04:04+0300\n"
 "PO-Revision-Date: 2015-04-04 04:04+0300\n"
diff --git a/po/it_IT.po b/po/it_IT.po
index 8818e2f..af8c8bb 100644
--- a/po/it_IT.po
+++ b/po/it_IT.po
@@ -6,7 +6,7 @@
 #
 msgid ""
 msgstr ""
-"Project-Id-Version: vdr-femon 2.2.1\n"
+"Project-Id-Version: vdr-femon 2.3.0\n"
 "Report-Msgid-Bugs-To: <see README>\n"
 "POT-Creation-Date: 2015-04-04 04:04+0300\n"
 "PO-Revision-Date: 2015-04-04 04:04+0300\n"
diff --git a/po/lt_LT.po b/po/lt_LT.po
index ee2b3fc..9266f18 100644
--- a/po/lt_LT.po
+++ b/po/lt_LT.po
@@ -5,7 +5,7 @@
 #
 msgid ""
 msgstr ""
-"Project-Id-Version: vdr-femon 2.2.1\n"
+"Project-Id-Version: vdr-femon 2.3.0\n"
 "Report-Msgid-Bugs-To: <see README>\n"
 "POT-Creation-Date: 2015-04-04 04:04+0300\n"
 "PO-Revision-Date: 2015-04-04 04:04+0300\n"
diff --git a/po/ru_RU.po b/po/ru_RU.po
index ac65c8b..4540479 100644
--- a/po/ru_RU.po
+++ b/po/ru_RU.po
@@ -5,7 +5,7 @@
 #
 msgid ""
 msgstr ""
-"Project-Id-Version: vdr-femon 2.2.1\n"
+"Project-Id-Version: vdr-femon 2.3.0\n"
 "Report-Msgid-Bugs-To: <see README>\n"
 "POT-Creation-Date: 2015-04-04 04:04+0300\n"
 "PO-Revision-Date: 2015-04-04 04:04+0300\n"
diff --git a/po/sk_SK.po b/po/sk_SK.po
index 5f40aa9..0f6474a 100644
--- a/po/sk_SK.po
+++ b/po/sk_SK.po
@@ -5,7 +5,7 @@
 #
 msgid ""
 msgstr ""
-"Project-Id-Version: vdr-femon 2.2.1\n"
+"Project-Id-Version: vdr-femon 2.3.0\n"
 "Report-Msgid-Bugs-To: <see README>\n"
 "POT-Creation-Date: 2015-04-04 04:04+0300\n"
 "PO-Revision-Date: 2015-04-04 04:04+0300\n"
diff --git a/po/uk_UA.po b/po/uk_UA.po
index 56efac1..d32ea1e 100644
--- a/po/uk_UA.po
+++ b/po/uk_UA.po
@@ -4,7 +4,7 @@
 # Yarema aka Knedlyk <yupadmin@gmail.com>, 2010.
 msgid ""
 msgstr ""
-"Project-Id-Version: vdr-femon 2.2.1\n"
+"Project-Id-Version: vdr-femon 2.3.0\n"
 "Report-Msgid-Bugs-To: <see README>\n"
 "POT-Creation-Date: 2015-04-04 04:04+0300\n"
 "PO-Revision-Date: 2015-04-04 04:04+0300\n"
diff --git a/po/zh_CN.po b/po/zh_CN.po
index b4b3865..ef80319 100644
--- a/po/zh_CN.po
+++ b/po/zh_CN.po
@@ -5,7 +5,7 @@
 #
 msgid ""
 msgstr ""
-"Project-Id-Version: vdr-femon 2.2.1\n"
+"Project-Id-Version: vdr-femon 2.3.0\n"
 "Report-Msgid-Bugs-To: <see README>\n"
 "POT-Creation-Date: 2015-04-04 04:04+0300\n"
 "PO-Revision-Date: 2015-04-04 04:04+0300\n"
diff --git a/po/zh_TW.po b/po/zh_TW.po
index e7d246d..67f94c6 100644
--- a/po/zh_TW.po
+++ b/po/zh_TW.po
@@ -5,7 +5,7 @@
 #
 msgid ""
 msgstr ""
-"Project-Id-Version: vdr-femon 2.2.1\n"
+"Project-Id-Version: vdr-femon 2.3.0\n"
 "Report-Msgid-Bugs-To: <see README>\n"
 "POT-Creation-Date: 2015-04-04 04:04+0300\n"
 "PO-Revision-Date: 2015-04-04 04:04+0300\n"
diff --git a/receiver.c b/receiver.c
index 4401dab..c5c1cef 100644
--- a/receiver.c
+++ b/receiver.c
@@ -101,7 +101,7 @@ void cFemonReceiver::Activate(bool onP)
      Deactivate();
 }
 
-void cFemonReceiver::Receive(uchar *dataP, int lengthP)
+void cFemonReceiver::Receive(const uchar *dataP, int lengthP)
 {
   // TS packet length: TS_SIZE
   if (Running() && (*dataP == TS_SYNC_BYTE) && (lengthP == TS_SIZE)) {
diff --git a/receiver.h b/receiver.h
index c4b5ecf..abd5c6e 100644
--- a/receiver.h
+++ b/receiver.h
@@ -59,7 +59,7 @@ private:
 
 protected:
   virtual void Activate(bool onP);
-  virtual void Receive(uchar *dataP, int lengthP);
+  virtual void Receive(const uchar *dataP, int lengthP);
   virtual void Action(void);
 
 public:
diff --git a/tools.c b/tools.c
index 3dafc52..9d012cd 100644
--- a/tools.c
+++ b/tools.c
@@ -110,7 +110,8 @@ cString getFrontendInfo(cDvbDevice *deviceP)
   uint16_t snr = 0;
   uint32_t ber = 0;
   uint32_t unc = 0;
-  cChannel *channel = Channels.GetByNumber(cDevice::CurrentChannel());
+  LOCK_CHANNELS_READ;
+  const cChannel *channel = Channels->GetByNumber(cDevice::CurrentChannel());
 
   if (!deviceP)
      return info;