diff --git a/src/common/RewindManager.cxx b/src/common/RewindManager.cxx
index 55ff40959..14fe54c81 100644
--- a/src/common/RewindManager.cxx
+++ b/src/common/RewindManager.cxx
@@ -38,7 +38,7 @@ void RewindManager::setup()
 {
   myLastTimeMachineAdd = false;
 
-  string prefix = myOSystem.settings().getBool("dev.settings") ? "dev." : "plr.";
+  const string& prefix = myOSystem.settings().getBool("dev.settings") ? "dev." : "plr.";
 
   mySize = myOSystem.settings().getInt(prefix + "tm.size");
   if(mySize != myStateList.capacity())
diff --git a/src/emucore/CartBUS.cxx b/src/emucore/CartBUS.cxx
index f3799d67b..4aeb0123a 100644
--- a/src/emucore/CartBUS.cxx
+++ b/src/emucore/CartBUS.cxx
@@ -64,7 +64,7 @@ CartridgeBUS::CartridgeBUS(const BytePtr& image, uInt32 size,
   myDisplayImage = myBUSRAM + DSRAM;
 
   // Create Thumbulator ARM emulator
-  string prefix = settings.getBool("dev.settings") ? "plr." : "dev.";
+  const string& prefix = settings.getBool("dev.settings") ? "plr." : "dev.";
   myThumbEmulator = make_unique<Thumbulator>(
     reinterpret_cast<uInt16*>(myImage), reinterpret_cast<uInt16*>(myBUSRAM),
     settings.getBool(prefix + "thumb.trapfatal"), Thumbulator::ConfigureFor::BUS, this
diff --git a/src/emucore/CartCDF.cxx b/src/emucore/CartCDF.cxx
index 599cc9bc8..41a9aa1f7 100644
--- a/src/emucore/CartCDF.cxx
+++ b/src/emucore/CartCDF.cxx
@@ -67,7 +67,7 @@ CartridgeCDF::CartridgeCDF(const BytePtr& image, uInt32 size,
   setVersion();
 
   // Create Thumbulator ARM emulator
-  string prefix = settings.getBool("dev.settings") ? "plr." : "dev.";
+  const string& prefix = settings.getBool("dev.settings") ? "plr." : "dev.";
   myThumbEmulator = make_unique<Thumbulator>(
     reinterpret_cast<uInt16*>(myImage), reinterpret_cast<uInt16*>(myCDFRAM),
     settings.getBool(prefix + "thumb.trapfatal"), myVersion ?
diff --git a/src/emucore/CartDPCPlus.cxx b/src/emucore/CartDPCPlus.cxx
index f6a3ab258..e457e1d4f 100644
--- a/src/emucore/CartDPCPlus.cxx
+++ b/src/emucore/CartDPCPlus.cxx
@@ -53,7 +53,7 @@ CartridgeDPCPlus::CartridgeDPCPlus(const BytePtr& image, uInt32 size,
   myFrequencyImage = myDisplayImage + 0x1000;
 
   // Create Thumbulator ARM emulator
-  string prefix = settings.getBool("dev.settings") ? "plr." : "dev.";
+  const string& prefix = settings.getBool("dev.settings") ? "plr." : "dev.";
   myThumbEmulator = make_unique<Thumbulator>
       (reinterpret_cast<uInt16*>(myImage),
        reinterpret_cast<uInt16*>(myDPCRAM),
diff --git a/src/emucore/tia/TIA.cxx b/src/emucore/tia/TIA.cxx
index 5886c25ed..7529ac0b0 100644
--- a/src/emucore/tia/TIA.cxx
+++ b/src/emucore/tia/TIA.cxx
@@ -200,7 +200,7 @@ void TIA::frameReset()
   memset(myBackBuffer, 0, 160 * TIAConstants::frameBufferHeight);
   memset(myFrontBuffer, 0, 160 * TIAConstants::frameBufferHeight);
   memset(myFramebuffer, 0, 160 * TIAConstants::frameBufferHeight);
-  enableColorLoss(mySettings.getBool("dev.settings") ? "dev.colorloss" : "plr.colorloss");
+  enableColorLoss(mySettings.getBool(mySettings.getBool("dev.settings") ? "dev.colorloss" : "plr.colorloss"));
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -