diff --git a/README.md b/README.md
index 7ca83c7..792c808 100644
--- a/README.md
+++ b/README.md
@@ -230,6 +230,9 @@ Work is in progress...
 
 ---
 ## Version history
+#### v0.9.340b
+- fixed compilation error audioVS1053Ex.cpp:181:5: error: 'sdog' was not declared in this scope
+
 #### v0.9.337b (homeassistant component)
 - fixed the error of subscribing to mqtt topic on some systems
 
diff --git a/yoRadio/src/audioVS1053/audioVS1053Ex.cpp b/yoRadio/src/audioVS1053/audioVS1053Ex.cpp
index 70975a3..2a81273 100644
--- a/yoRadio/src/audioVS1053/audioVS1053Ex.cpp
+++ b/yoRadio/src/audioVS1053/audioVS1053Ex.cpp
@@ -178,18 +178,15 @@ void Audio::control_mode_off()
 {
     CS_HIGH();                                     // End control mode
     spi_VS1053->endTransaction();                  // Allow other SPI users
-    sdog.giveMutex();
 }
 void Audio::control_mode_on()
 {
-    sdog.takeMutex();
     spi_VS1053->beginTransaction(VS1053_SPI_CTL);   // Prevent other SPI users
     DCS_HIGH();                                     // Bring slave in control mode
     CS_LOW();
 }
 void Audio::data_mode_on()
 {
-    sdog.takeMutex();
     spi_VS1053->beginTransaction(VS1053_SPI_DATA);  // Prevent other SPI users
     CS_HIGH();                                      // Bring slave in data mode
     DCS_LOW();
@@ -199,7 +196,6 @@ void Audio::data_mode_off()
     //digitalWrite(dcs_pin, HIGH);              // End data mode
     DCS_HIGH();
     spi_VS1053->endTransaction();                       // Allow other SPI users
-    sdog.giveMutex();
 }
 //---------------------------------------------------------------------------------------------------------------------
 uint16_t Audio::read_register(uint8_t _reg)
diff --git a/yoRadio/src/core/options.h b/yoRadio/src/core/options.h
index 6c8255d..b77d0c7 100644
--- a/yoRadio/src/core/options.h
+++ b/yoRadio/src/core/options.h
@@ -1,7 +1,7 @@
 #ifndef options_h
 #define options_h
 
-#define YOVERSION "0.9.337b"
+#define YOVERSION "0.9.340b"
 
 /*******************************************************
 DO NOT EDIT THIS FILE.