diff --git a/mythplugins/mythmusic/mythmusic/playlistcontainer.h b/mythplugins/mythmusic/mythmusic/playlistcontainer.h
@@ -62,12 +62,12 @@ class PlaylistContainer
 
     void            clearActive();
 
-    bool            doneLoading(){return m_doneLoading;}
+    bool            doneLoading() const{return m_doneLoading;}
 
     bool            cleanOutThreads();
 
     void            FillIntelliWeights(int &rating, int &playcount,
-                                       int &lastplay, int &random);
+                                       int &lastplay, int &random) const;
     QList<Playlist*> *getPlaylists(void) { return m_allPlaylists; }
     QStringList       getPlaylistNames(void);
 

diff --git a/mythplugins/mythmusic/mythmusic/pls.h b/mythplugins/mythmusic/mythmusic/pls.h
@@ -24,7 +24,7 @@ class PlayListFileEntry
 
     QString File(void) { return m_file; }
     QString Title(void) { return m_title; }
-    int Length(void) { return m_length; }
+    int Length(void) const { return m_length; }
 
     void setFile(const QString &f) { m_file = f; }
     void setTitle(const QString &t) { m_title = t; }

diff --git a/mythplugins/mythmusic/mythmusic/smartplaylist.cpp b/mythplugins/mythmusic/mythmusic/smartplaylist.cpp
@@ -287,7 +287,7 @@ QString getSQLFieldName(const QString &fieldName)
 ///////////////////////////////////////////////////////////////////////
 */
 
-QString SmartPLCriteriaRow::getSQL(void)
+QString SmartPLCriteriaRow::getSQL(void) const
 {
     if (m_field.isEmpty())
         return QString();
@@ -300,7 +300,7 @@ QString SmartPLCriteriaRow::getSQL(void)
 }
 
 // return false on error
-bool SmartPLCriteriaRow::saveToDatabase(int smartPlaylistID)
+bool SmartPLCriteriaRow::saveToDatabase(int smartPlaylistID) const
 {
     // save playlistitem to database
 
@@ -326,7 +326,7 @@ bool SmartPLCriteriaRow::saveToDatabase(int smartPlaylistID)
     return true;
 }
 
-QString SmartPLCriteriaRow::toString(void)
+QString SmartPLCriteriaRow::toString(void) const
 {
     SmartPLOperator *PLOperator = lookupOperator(m_operator);
     if (PLOperator)

diff --git a/mythplugins/mythmusic/mythmusic/smartplaylist.h b/mythplugins/mythmusic/mythmusic/smartplaylist.h
@@ -54,11 +54,11 @@ class SmartPLCriteriaRow
     SmartPLCriteriaRow(void) = default;
     ~SmartPLCriteriaRow(void) = default;
 
-    QString getSQL(void);
+    QString getSQL(void) const;
 
-    bool saveToDatabase(int smartPlaylistID);
+    bool saveToDatabase(int smartPlaylistID) const;
 
-    QString toString(void);
+    QString toString(void) const;
 
   public:
     QString m_field;

diff --git a/mythplugins/mythmusic/mythmusic/synaesthesia.cpp b/mythplugins/mythmusic/mythmusic/synaesthesia.cpp
@@ -222,7 +222,7 @@ void Synaesthesia::coreInit(void)
 #define lastOutput ((unsigned char*)m_lastOutputBmp.data)
 #define lastLastOutput ((unsigned char*)m_lastLastOutputBmp.data)
 
-void Synaesthesia::addPixel(int x, int y, int br1, int br2)
+void Synaesthesia::addPixel(int x, int y, int br1, int br2) const
 {
     if (x < 0 || x > m_outWidth || y < 0 || y >= m_outHeight)
         return;
@@ -250,15 +250,15 @@ void Synaesthesia::addPixelFast(unsigned char *p, int br1, int br2)
         p[1] = 255;
 }
 
-unsigned char Synaesthesia::getPixel(int x, int y, int where)
+unsigned char Synaesthesia::getPixel(int x, int y, int where) const
 {
     if (x < 0 || y < 0 || x >= m_outWidth || y >= m_outHeight)
         return 0;
 
     return lastOutput[where];
 }
 
-void Synaesthesia::fadeFade(void)
+void Synaesthesia::fadeFade(void) const
 {
     auto *ptr = (uint32_t *)output;
     int i = m_outWidth * m_outHeight * 2 / sizeof(uint32_t);

diff --git a/mythplugins/mythmusic/mythmusic/synaesthesia.h b/mythplugins/mythmusic/mythmusic/synaesthesia.h
@@ -35,15 +35,15 @@ class Synaesthesia : public VisualBase
     void fft(double *x, double *y);
     void setStarSize(double lsize);
 
-    inline void addPixel(int x, int y, int br1, int br2);
+    inline void addPixel(int x, int y, int br1, int br2) const;
     static inline void addPixelFast(unsigned char *p, int br1, int br2);
-    inline unsigned char getPixel(int x, int y, int where);
+    inline unsigned char getPixel(int x, int y, int where) const;
 
     inline void fadePixelWave(int x, int y, int where, int step);
     void fadeWave(void);
     inline void fadePixelHeat(int x, int y, int where, int step);
     void fadeHeat(void);
-    void fadeFade(void);
+    void fadeFade(void) const;
     void fade(void);
 
     QSize m_size                 {0,0};

diff --git a/mythplugins/mythweather/mythweather/weatherScreen.h b/mythplugins/mythweather/mythweather/weatherScreen.h
@@ -42,11 +42,11 @@ class WeatherScreen : public MythScreenType
     bool containsKey(const QString &key) { return m_dataValueMap.contains(key); }
     virtual bool canShowScreen();
     void setUnits(units_t units) { m_units = units; }
-    units_t getUnits() { return m_units; }
+    units_t getUnits() const { return m_units; }
     virtual bool usingKeys() { return false; }
-    bool inUse() { return m_inuse; }
+    bool inUse() const { return m_inuse; }
     void setInUse(bool inuse) { m_inuse = inuse; }
-    int getId() { return m_id; }
+    int getId() const { return m_id; }
 
   signals:
     void screenReady(WeatherScreen *);

diff --git a/mythplugins/mythweather/mythweather/weatherSource.h b/mythplugins/mythweather/mythweather/weatherSource.h
@@ -47,12 +47,12 @@ class WeatherSource : public QObject
     explicit WeatherSource(ScriptInfo *info);
     ~WeatherSource() override;
 
-    bool isReady() { return m_ready; }
+    bool isReady() const { return m_ready; }
     QString getVersion() { return m_info->version; }
     QString getName() { return m_info->name; }
     QString getAuthor() { return m_info->author; }
     QString getEmail() { return m_info->email; }
-    units_t getUnits() { return m_units; }
+    units_t getUnits() const { return m_units; }
     void setUnits(units_t units) { m_units = units; }
     QStringList getLocationList(const QString &str);
     void setLocale(const QString &locale) { m_locale = locale; }
@@ -69,7 +69,7 @@ class WeatherSource : public QObject
     void startUpdateTimer() { m_updateTimer->start(m_info->updateTimeout); }
     void stopUpdateTimer() { m_updateTimer->stop(); }
 
-    bool inUse() { return m_inuse; }
+    bool inUse() const { return m_inuse; }
     void setInUse(bool inuse) { m_inuse = inuse; }
 
     int getId() { return m_info->id; }

diff --git a/mythplugins/mythzoneminder/mythzmserver/zmserver.cpp b/mythplugins/mythzoneminder/mythzmserver/zmserver.cpp
@@ -1875,7 +1875,7 @@ int ZMServer::getFrame(unsigned char *buffer, int bufferSize, MONITOR *monitor)
     return monitor->m_width * monitor->m_height * 3;
 }
 
-string ZMServer::getZMSetting(const string &setting)
+string ZMServer::getZMSetting(const string &setting) const
 {
     string result;
     string sql("SELECT Name, Value FROM Config ");

diff --git a/mythplugins/mythzoneminder/mythzmserver/zmserver.h b/mythplugins/mythzoneminder/mythzmserver/zmserver.h
@@ -246,7 +246,7 @@ class ZMServer
     bool processRequest(char* buf, int nbytes);
 
   private:
-    string getZMSetting(const string &setting);
+    string getZMSetting(const string &setting) const;
     bool send(const string &s) const;
     bool send(const string &s, const unsigned char *buffer, int dataLen) const;
     void sendError(const string &error);

diff --git a/mythplugins/mythzoneminder/mythzoneminder/zmclient.h b/mythplugins/mythzoneminder/mythzoneminder/zmclient.h
@@ -32,7 +32,7 @@ class MPUBLIC ZMClient : public QObject
 
     // Used to actually connect to an ZM server
     bool connectToHost(const QString &hostname, unsigned int port);
-    bool connected(void) { return m_bConnected; }
+    bool connected(void) const { return m_bConnected; }
 
     bool checkProtoVersion(void);
 
@@ -61,7 +61,7 @@ class MPUBLIC ZMClient : public QObject
     void setMonitorFunction(int monitorID, const QString &function, bool enabled);
     bool updateAlarmStates(void);
 
-    bool isMiniPlayerEnabled(void) { return m_isMiniPlayerEnabled; }
+    bool isMiniPlayerEnabled(void) const { return m_isMiniPlayerEnabled; }
     void setIsMiniPlayerEnabled(bool enabled) { m_isMiniPlayerEnabled = enabled; }
 
     void saveNotificationMonitors(void);