diff --git a/code/nel/src/3d/driver/opengl/stdopengl.h b/code/nel/src/3d/driver/opengl/stdopengl.h
index 2167324f0..3066a778a 100644
--- a/code/nel/src/3d/driver/opengl/stdopengl.h
+++ b/code/nel/src/3d/driver/opengl/stdopengl.h
@@ -101,9 +101,9 @@
 #include "nel/3d/index_buffer.h"
 
 #ifdef NL_OS_MAC
+#include <AvailabilityMacros.h>
 #if defined(MAC_OS_X_VERSION_10_6) && MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_6
 #define NL_MAC_VERSION_10_6_UP
-#else
 #endif
 #endif
 
diff --git a/code/ryzom/client/src/client.cpp b/code/ryzom/client/src/client.cpp
index 1ec2b0643..be7cf1647 100644
--- a/code/ryzom/client/src/client.cpp
+++ b/code/ryzom/client/src/client.cpp
@@ -366,6 +366,11 @@ int main(int argc, char **argv)
 	// init the Nel context
 	CApplicationContext *appContext = new CApplicationContext;
 
+	// disable nldebug messages in logs in Release
+#ifdef NL_RELEASE
+	DisableNLDebug = true;
+#endif
+
 	createDebug();
 
 	INelContext::getInstance().setWindowedApplication(true);
diff --git a/code/ryzom/client/src/misc.cpp b/code/ryzom/client/src/misc.cpp
index 775e9cc41..bb3625c4b 100644
--- a/code/ryzom/client/src/misc.cpp
+++ b/code/ryzom/client/src/misc.cpp
@@ -1477,14 +1477,30 @@ bool getRyzomModes(std::vector<NL3D::UDriver::CMode> &videoModes, std::vector<st
 			if (videoModes[i].Width == videoModes[nFoundMode].Width && videoModes[i].Height == videoModes[nFoundMode].Height)
 			{
 				uint freq = videoModes[i].Frequency;
+				std::string freqStr = toString(freq);
 
-				// if frequency is 0, take the first one else use the exact one
-				if (nFoundStringFreq == -1 && ((ClientCfg.Frequency == 0) || (freq == ClientCfg.Frequency)))
+				bool bFound = false;
+
+				// check if frequency already found in list
+				for (j = 0; j < (sint)stringFreqList.size(); ++j)
 				{
-					nFoundStringFreq = stringFreqList.size();
+					if (stringFreqList[j] == freqStr)
+					{
+						bFound = true;
+						break;
+					}
 				}
 
-				stringFreqList.push_back(toString(freq));
+				if (!bFound)
+				{
+					// if frequency is 0, take the first one else use the exact one
+					if (nFoundStringFreq == -1 && ((ClientCfg.Frequency == 0) || (freq == ClientCfg.Frequency)))
+					{
+						nFoundStringFreq = stringFreqList.size();
+					}
+
+					stringFreqList.push_back(freqStr);
+				}
 			}
 		}
 	}