diff --git a/extern/vgsound_emu-modified/CHANGELOG.md b/extern/vgsound_emu-modified/CHANGELOG.md
index bf1e6677..305e8337 100644
--- a/extern/vgsound_emu-modified/CHANGELOG.md
+++ b/extern/vgsound_emu-modified/CHANGELOG.md
@@ -2,6 +2,10 @@
 
 ## Important changes
 
+### V 2.1.1 (2022-10-20)
+
+Add C++11 detection for CMake
+
 ### V 2.1.0 (2022-09-08)
 
 Move source folder into vgsound_emu folder
diff --git a/extern/vgsound_emu-modified/CMakeLists.txt b/extern/vgsound_emu-modified/CMakeLists.txt
index 17e14291..f1ba138e 100644
--- a/extern/vgsound_emu-modified/CMakeLists.txt
+++ b/extern/vgsound_emu-modified/CMakeLists.txt
@@ -8,9 +8,11 @@
 
 cmake_minimum_required(VERSION 3.0)
 project(vgsound_emu
-	VERSION 2.1.0
+	VERSION 2.1.1
 	LANGUAGES CXX)
 
+enable_language(CXX)
+
 option(VGSOUND_EMU_ES5504 "Use ES5504 core" ON)
 option(VGSOUND_EMU_ES5505 "Use ES5505 core" ON)
 option(VGSOUND_EMU_ES5506 "Use ES5506 core" ON)
@@ -31,19 +33,80 @@ message(STATUS "Generator: ${CMAKE_GENERATOR}")
 message(STATUS "Extra generator: ${CMAKE_EXTRA_GENERATOR}")
 message(STATUS "Make program: ${CMAKE_MAKE_PROGRAM}")
 
+if(${CMAKE_VERSION} VERSION_GREATER_EQUAL "3.1.0")
+	message(STATUS "Generating C++11 compile features:")
+
+	if(${CMAKE_VERSION} VERSION_GREATER_EQUAL "3.8.0")
+		set(cxx_features cxx_std_11)
+	else()
+		set(cxx_features
+			cxx_template_template_parameters
+			cxx_alias_templates
+			cxx_alignas
+			cxx_alignof
+			cxx_attributes
+			cxx_auto_type
+			cxx_constexpr
+			cxx_decltype
+			cxx_decltype_incomplete_return_types
+			cxx_default_function_template_args
+			cxx_defaulted_functions
+			cxx_defaulted_move_initializers
+			cxx_delegating_constructors
+			cxx_deleted_functions
+			cxx_enum_forward_declarations
+			cxx_explicit_conversions
+			cxx_extended_friend_declarations
+			cxx_extern_templates
+			cxx_final
+			cxx_func_identifier
+			cxx_generalized_initializers
+			cxx_inheriting_constructors
+			cxx_inline_namespaces
+			cxx_lambdas
+			cxx_local_type_template_args
+			cxx_long_long_type
+			cxx_noexcept
+			cxx_nonstatic_member_init
+			cxx_nullptr
+			cxx_override
+			cxx_range_for
+			cxx_raw_string_literals
+			cxx_reference_qualified_functions
+			cxx_right_angle_brackets
+			cxx_rvalue_references
+			cxx_sizeof_member
+			cxx_static_assert
+			cxx_strong_enums
+			cxx_thread_local
+			cxx_trailing_return_types
+			cxx_unicode_literals
+			cxx_uniform_initialization
+			cxx_unrestricted_unions
+			cxx_user_literals
+			cxx_variadic_macros
+			cxx_variadic_templates)
+	endif()
+
+	message(STATUS "${cxx_features}")
+endif()
+
 set(CORE_SOURCE "")
 set(EMU_SOURCE "")
 
 # Core functions
 list(APPEND CORE_SOURCE
-	vgsound_emu/src/core/util.hpp
+	vgsound_emu/src/core/core.hpp
+	vgsound_emu/src/core/util/clock_pulse.hpp
+	vgsound_emu/src/core/util/fifo.hpp
+	vgsound_emu/src/core/util/mem_intf.hpp
 )
 
 # Dialogic ADPCM
 if(VGSOUND_EMU_MSM6295)
 	list(APPEND CORE_SOURCE
-		vgsound_emu/src/core/vox/vox.cpp
 		vgsound_emu/src/core/vox/vox.hpp
+		vgsound_emu/src/core/vox/vox.cpp
 	)
 	message(STATUS "Using Dialogic ADPCM core")
 endif()
@@ -156,6 +219,18 @@ if(VGSOUND_EMU_X1_010)
 endif()
 
 add_library(vgsound_emu STATIC ${CORE_SOURCE} ${EMU_SOURCE})
+
+if(${CMAKE_VERSION} VERSION_GREATER_EQUAL "3.1.0")
+	set_target_properties(vgsound_emu
+		PROPERTIES
+		CXX_STANDARD 11
+		CXX_STANDARD_REQUIRED ON
+		CXX_EXTENSIONS OFF)
+	target_compile_features(vgsound_emu PRIVATE ${cxx_features})
+	message(STATUS "C++11 Enabled")
+endif()
+
 target_include_directories(${PROJECT_NAME} INTERFACE ${CMAKE_CURRENT_SOURCE_DIR})
 
-# target_compile_options(vgsound_emu PRIVATE -Wall -Werror)
\ No newline at end of file
+# for Test purpose (GCC)
+# target_compile_options(vgsound_emu PRIVATE -Wall -Wextra -Werror)
\ No newline at end of file
diff --git a/extern/vgsound_emu-modified/README.md b/extern/vgsound_emu-modified/README.md
index b24e2888..82114756 100644
--- a/extern/vgsound_emu-modified/README.md
+++ b/extern/vgsound_emu-modified/README.md
@@ -1,6 +1,6 @@
 # vgsound_emu V2 (modified)
 
-This is a library of video game sound chip emulation cores. useful for emulators, chiptune trackers, or players.
+This is a C++ library of video game sound chip emulation cores. useful for emulators, chiptune trackers, or players.
 
 This is a modified version of vgsound_emu, tailored for Furnace.
 
@@ -46,7 +46,8 @@ See [here](https://gitlab.com/cam900/vgsound_emu/-/blob/main/LICENSE) for detail
 
 ### dependencies
 
-- CMake
+- C++11 (or later)
+- CMake (3.1 or later is recommended)
 - git (for source repository management)
 - MSVC or GCC or Clang (for compile)
 
@@ -59,7 +60,7 @@ git clone https://gitlab.com/cam900/vgsound_emu.git
 cd vgsound_emu
 ```
 
-### Compile
+### Compile with CMake
 
 #### MSVC