diff --git a/src/common/Base.cxx b/src/common/Base.cxx
index ee125ee7e..9ae15ce34 100644
--- a/src/common/Base.cxx
+++ b/src/common/Base.cxx
@@ -22,7 +22,7 @@ namespace Common {
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 string Base::toString(int value, Common::Base::Fmt outputBase)
 {
-  static char vToS_buf[32];  // NOLINT - One place where C-style is acceptable
+  static char vToS_buf[32];  // NOLINT : One place where C-style is acceptable
 
   if(outputBase == Base::Fmt::_DEFAULT)
     outputBase = myDefaultBase;
diff --git a/src/common/HighScoresManager.cxx b/src/common/HighScoresManager.cxx
index 59946b29b..492ada82b 100644
--- a/src/common/HighScoresManager.cxx
+++ b/src/common/HighScoresManager.cxx
@@ -69,7 +69,7 @@ Int16 HighScoresManager::peek(uInt16 addr) const
 {
   if (myOSystem.hasConsole())
   {
-    if(addr < 0x100u || myOSystem.console().cartridge().internalRamSize() == 0)
+    if(addr < 0x100U || myOSystem.console().cartridge().internalRamSize() == 0)
       return myOSystem.console().system().peek(addr);
     else
       return myOSystem.console().cartridge().internalRamGetValue(addr);
diff --git a/src/common/KeyMap.cxx b/src/common/KeyMap.cxx
index 559a7128a..6fdc28ffc 100644
--- a/src/common/KeyMap.cxx
+++ b/src/common/KeyMap.cxx
@@ -56,7 +56,7 @@ namespace {
     return serializedMask.size() == 1 ? serializedMask.at(0) : serializedMask;
   }
 
-  int deserializeModkeyMask(json serializedMask)
+  int deserializeModkeyMask(const json& serializedMask)
   {
     if(serializedMask.is_null()) return StellaMod::KBDM_NONE;
     if(!serializedMask.is_array()) return serializedMask.get<StellaMod>();
diff --git a/src/common/repository/sqlite/KeyValueRepositorySqlite.cxx b/src/common/repository/sqlite/KeyValueRepositorySqlite.cxx
index d27dd34b0..7264c4cb6 100644
--- a/src/common/repository/sqlite/KeyValueRepositorySqlite.cxx
+++ b/src/common/repository/sqlite/KeyValueRepositorySqlite.cxx
@@ -43,7 +43,7 @@ std::map<string, Variant> KeyValueRepositorySqlite::load()
     myStmtSelect->reset();
   }
   catch (const SqliteError& err) {
-    Logger::info(err.message);
+    Logger::info(err.what());
   }
 
   return values;
@@ -69,7 +69,7 @@ void KeyValueRepositorySqlite::save(const std::map<string, Variant>& values)
     tx.commit();
   }
   catch (const SqliteError& err) {
-    Logger::info(err.message);
+    Logger::info(err.what());
   }
 }
 
@@ -87,7 +87,7 @@ void KeyValueRepositorySqlite::save(const string& key, const Variant& value)
     myStmtInsert->reset();
   }
   catch (const SqliteError& err) {
-    Logger::info(err.message);
+    Logger::info(err.what());
   }
 }
 
diff --git a/src/common/repository/sqlite/SettingsDb.cxx b/src/common/repository/sqlite/SettingsDb.cxx
index 3dee9e8a0..15116aa4e 100644
--- a/src/common/repository/sqlite/SettingsDb.cxx
+++ b/src/common/repository/sqlite/SettingsDb.cxx
@@ -39,7 +39,7 @@ bool SettingsDb::initialize()
     mySettingsRepository->initialize();
   }
   catch (const SqliteError& err) {
-    Logger::info("sqlite DB " + databaseFileName() + " failed to initialize: " + err.message);
+    Logger::info("sqlite DB " + databaseFileName() + " failed to initialize: " + err.what());
 
     myDb.reset();
     mySettingsRepository.reset();
diff --git a/src/common/repository/sqlite/SqliteDatabase.cxx b/src/common/repository/sqlite/SqliteDatabase.cxx
index 3110e9df8..4b1edc09e 100644
--- a/src/common/repository/sqlite/SqliteDatabase.cxx
+++ b/src/common/repository/sqlite/SqliteDatabase.cxx
@@ -66,7 +66,7 @@ void SqliteDatabase::initialize()
     }
 
     throw SqliteError("unable to initialize sqlite DB for unknown reason");
-  };
+  }
 
   exec("PRAGMA journal_mode=WAL");
 
diff --git a/src/common/repository/sqlite/SqliteError.hxx b/src/common/repository/sqlite/SqliteError.hxx
index 603828f9e..68379b52a 100644
--- a/src/common/repository/sqlite/SqliteError.hxx
+++ b/src/common/repository/sqlite/SqliteError.hxx
@@ -21,12 +21,16 @@
 #include <sqlite3.h>
 #include "bspf.hxx"
 
-struct SqliteError {
-  explicit SqliteError(const string& _message) : message(_message) {}
+class SqliteError : public std::exception
+{
+  public:
+    explicit SqliteError(const string& message) : myMessage(message) { }
+    explicit SqliteError(sqlite3* handle) : myMessage(sqlite3_errmsg(handle)) { }
 
-  explicit SqliteError(sqlite3* handle) : message(sqlite3_errmsg(handle)) {}
+    const char* what() const noexcept override { return myMessage.c_str(); }
 
-  const string message;
+  private:
+    const string myMessage;
 };
 
 #endif // SQLITE_ERROR_HXX
diff --git a/src/common/repository/sqlite/SqliteStatement.cxx b/src/common/repository/sqlite/SqliteStatement.cxx
index 516499fae..5043e2fc8 100644
--- a/src/common/repository/sqlite/SqliteStatement.cxx
+++ b/src/common/repository/sqlite/SqliteStatement.cxx
@@ -18,7 +18,7 @@
 #include "SqliteError.hxx"
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-SqliteStatement::SqliteStatement(sqlite3* handle, string sql)
+SqliteStatement::SqliteStatement(sqlite3* handle, const string& sql)
   : myHandle(handle)
 {
   if (sqlite3_prepare_v2(handle, sql.c_str(), -1, &myStmt, nullptr) != SQLITE_OK)
diff --git a/src/common/repository/sqlite/SqliteStatement.hxx b/src/common/repository/sqlite/SqliteStatement.hxx
index 911753cb0..c1d50ca11 100644
--- a/src/common/repository/sqlite/SqliteStatement.hxx
+++ b/src/common/repository/sqlite/SqliteStatement.hxx
@@ -25,7 +25,7 @@
 class SqliteStatement {
   public:
 
-    SqliteStatement(sqlite3* handle, string sql);
+    SqliteStatement(sqlite3* handle, const string& sql);
 
     ~SqliteStatement();
 
diff --git a/src/debugger/gui/Cart3EWidget.cxx b/src/debugger/gui/Cart3EWidget.cxx
index 9e0822b51..4d5f79a7c 100644
--- a/src/debugger/gui/Cart3EWidget.cxx
+++ b/src/debugger/gui/Cart3EWidget.cxx
@@ -117,7 +117,7 @@ void Cartridge3EWidget::loadConfig()
     myBankWidgets[1]->setSelectedIndex(bank - myCart.romBankCount(), oldBank != bank);
   }
 
-  CartDebugWidget::loadConfig();  // Intentionally calling grand-parent method
+  CartDebugWidget::loadConfig();  // NOLINT : Intentionally calling grand-parent method
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
diff --git a/src/debugger/gui/DataGridRamWidget.cxx b/src/debugger/gui/DataGridRamWidget.cxx
index 7445f1d90..96e11a004 100644
--- a/src/debugger/gui/DataGridRamWidget.cxx
+++ b/src/debugger/gui/DataGridRamWidget.cxx
@@ -41,7 +41,7 @@ string DataGridRamWidget::getToolTip(const Common::Point& pos) const
 
   const Int32 addr = _addrList[idx];
   const string label = _ram.getLabel(addr);
-  const string tip = DataGridWidget::getToolTip(pos);
+  string tip = DataGridWidget::getToolTip(pos);
 
   if(label.empty())
     return tip;
diff --git a/src/debugger/gui/ToggleBitWidget.cxx b/src/debugger/gui/ToggleBitWidget.cxx
index 629e58c57..66868ac43 100644
--- a/src/debugger/gui/ToggleBitWidget.cxx
+++ b/src/debugger/gui/ToggleBitWidget.cxx
@@ -89,7 +89,7 @@ string ToggleBitWidget::getToolTip(const Common::Point& pos) const
   if(idx.y < 0)
     return EmptyString;
 
-  const string tip = ToggleWidget::getToolTip(pos);
+  string tip = ToggleWidget::getToolTip(pos);
 
   if(idx.x < static_cast<int>(_labelList.size()))
   {
diff --git a/src/emucore/Console.hxx b/src/emucore/Console.hxx
index aa9a75f38..59048239f 100644
--- a/src/emucore/Console.hxx
+++ b/src/emucore/Console.hxx
@@ -185,11 +185,6 @@ class Console : public Serializable, public ConsoleIO
      */
     EmulationTiming& emulationTiming() { return myEmulationTiming; }
 
-    /**
-      Retrieve the current game's refresh rate, or 0 if no game.
-    */
-    int refreshRate() const;
-
   public:
     /**
       Toggle between NTSC/PAL/SECAM (and variants) display format.
diff --git a/src/emucore/FBSurface.cxx b/src/emucore/FBSurface.cxx
index 16030b579..48baa04a7 100644
--- a/src/emucore/FBSurface.cxx
+++ b/src/emucore/FBSurface.cxx
@@ -184,10 +184,10 @@ void FBSurface::drawChar(const GUI::Font& font, uInt8 chr,
   }
   else
   {
-    bbw = desc.bbx[chr].w;
-    bbh = desc.bbx[chr].h;
-    bbx = desc.bbx[chr].x;
-    bby = desc.bbx[chr].y;
+    bbw = desc.bbx[chr].w;  // NOLINT
+    bbh = desc.bbx[chr].h;  // NOLINT
+    bbx = desc.bbx[chr].x;  // NOLINT
+    bby = desc.bbx[chr].y;  // NOLINT
   }
 
   uInt32 cx = tx + bbx;
diff --git a/src/emucore/FrameBuffer.cxx b/src/emucore/FrameBuffer.cxx
index 0fb7fe622..6b8e9ef01 100644
--- a/src/emucore/FrameBuffer.cxx
+++ b/src/emucore/FrameBuffer.cxx
@@ -1288,6 +1288,8 @@ void FrameBuffer::setCursorState()
       showCursor(true);       // +UI, +Emulation
       myGrabMouse = false; // disable grab while cursor is shown in emulation
       break;
+    default:
+      break;
   }
 
   myBackend->grabMouse(emulation && (analog || alwaysUseMouse) && myGrabMouse);
diff --git a/src/gui/AboutDialog.cxx b/src/gui/AboutDialog.cxx
index 426adbeeb..e89c89c9a 100644
--- a/src/gui/AboutDialog.cxx
+++ b/src/gui/AboutDialog.cxx
@@ -172,7 +172,7 @@ void AboutDialog::updateStrings(int page, int lines, string& title)
       return;
   }
 
-  while(i < lines)
+  while(i < lines)  // NOLINT : i changes in lambda above
     ADD_ALINE();
 }
 
diff --git a/src/gui/HelpDialog.cxx b/src/gui/HelpDialog.cxx
index 0b08ca0cc..cf0854a73 100644
--- a/src/gui/HelpDialog.cxx
+++ b/src/gui/HelpDialog.cxx
@@ -174,7 +174,7 @@ void HelpDialog::updateStrings(uInt8 page, uInt8 lines, string& title)
       break;
   }
 
-  while(i < lines)
+  while(i < lines)  // NOLINT : i changes in lambda above
     ADD_LINE();
 }
 
diff --git a/src/gui/HighScoresDialog.hxx b/src/gui/HighScoresDialog.hxx
index a62351990..e81b3e255 100644
--- a/src/gui/HighScoresDialog.hxx
+++ b/src/gui/HighScoresDialog.hxx
@@ -45,11 +45,11 @@ using json = nlohmann::json;
 class HighScoresDialog : public Dialog
 {
   public:
-    static const uInt32 NUM_RANKS = 10;
+    static constexpr uInt32 NUM_RANKS = 10;
 
     HighScoresDialog(OSystem& osystem, DialogContainer& parent,
                      int max_w, int max_h, Menu::AppMode mode);
-    virtual ~HighScoresDialog();
+    ~HighScoresDialog() override;
 
   protected:
     void loadConfig() override;
diff --git a/src/gui/HighScoresMenu.hxx b/src/gui/HighScoresMenu.hxx
index 68c4cc1c4..c1cf85b62 100644
--- a/src/gui/HighScoresMenu.hxx
+++ b/src/gui/HighScoresMenu.hxx
@@ -35,7 +35,7 @@ class HighScoresMenu : public DialogContainer
       Create a new menu stack
     */
     explicit HighScoresMenu(OSystem& osystem);
-    virtual ~HighScoresMenu();
+    ~HighScoresMenu() override;
 
   private:
     Dialog* baseDialog() override;
diff --git a/src/gui/ProgressDialog.cxx b/src/gui/ProgressDialog.cxx
index 80aafc8c4..7f0965fbc 100644
--- a/src/gui/ProgressDialog.cxx
+++ b/src/gui/ProgressDialog.cxx
@@ -138,15 +138,8 @@ void ProgressDialog::incProgress()
 void ProgressDialog::handleCommand(CommandSender* sender, int cmd,
                                    int data, int id)
 {
-  switch(cmd)
-  {
-    case Event::UICancel:
-      myIsCancelled = true;
-      break;
-
-    default:
-      Dialog::handleCommand(sender, cmd, data, 0);
-      break;
-  }
+  if(cmd == Event::UICancel)
+    myIsCancelled = true;
+  else
+    Dialog::handleCommand(sender, cmd, data, 0);
 }
-
diff --git a/src/gui/R77HelpDialog.cxx b/src/gui/R77HelpDialog.cxx
index 1e4601ced..b72efb0b2 100644
--- a/src/gui/R77HelpDialog.cxx
+++ b/src/gui/R77HelpDialog.cxx
@@ -167,7 +167,7 @@ void R77HelpDialog::updateStrings(uInt8 page, uInt8 lines, string& title)
       return;
   }
 
-  while (i < lines)
+  while (i < lines) // NOLINT : i changes in lambda above
     ADD_BIND();
 }
 
diff --git a/src/gui/TimeMachineDialog.cxx b/src/gui/TimeMachineDialog.cxx
index 594ed5036..97020c825 100644
--- a/src/gui/TimeMachineDialog.cxx
+++ b/src/gui/TimeMachineDialog.cxx
@@ -393,18 +393,10 @@ void TimeMachineDialog::handleKeyUp(StellaKey key, StellaMod mod)
 
   Event::Type event = instance().eventHandler().eventForKey(EventMode::kEmulationMode, key, mod);
 
-  switch (event)
-  {
-    case Event::TogglePlayBackMode:
-      handleCommand(nullptr, kPlayBack, 0, 0);
-      break;
-
-    default:
-      if (key == KBDK_SPACE)
-        handleCommand(nullptr, kPlayBack, 0, 0);
-      else
-        Dialog::handleKeyUp(key, mod);
-  }
+  if(event == Event::TogglePlayBackMode || key == KBDK_SPACE)
+    handleCommand(nullptr, kPlayBack, 0, 0);
+  else
+    Dialog::handleKeyUp(key, mod);
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -