diff --git a/extern/vgsound_emu-modified/vgsound_emu/src/es550x/es5505.hpp b/extern/vgsound_emu-modified/vgsound_emu/src/es550x/es5505.hpp
index 34782f104..4c8454c88 100644
--- a/extern/vgsound_emu-modified/vgsound_emu/src/es550x/es5505.hpp
+++ b/extern/vgsound_emu-modified/vgsound_emu/src/es550x/es5505.hpp
@@ -35,7 +35,7 @@ class es5505_core : public es550x_shared_core
 
 				inline s32 clamp16(s32 in) { return clamp(in, -0x8000, 0x7fff); }
 
-				inline void clamp16(output_t src)
+				inline void clamp16(output_t &src)
 				{
 					m_left	= clamp16(src.left());
 					m_right = clamp16(src.right());
@@ -76,7 +76,7 @@ class es5505_core : public es550x_shared_core
 					return *this;
 				}
 
-				output_t &operator=(output_t src)
+				output_t &operator=(output_t &src)
 				{
 					clamp16(src);
 					return *this;
diff --git a/extern/vgsound_emu-modified/vgsound_emu/src/es550x/es5506.hpp b/extern/vgsound_emu-modified/vgsound_emu/src/es550x/es5506.hpp
index 84a6077de..53713cfbe 100644
--- a/extern/vgsound_emu-modified/vgsound_emu/src/es550x/es5506.hpp
+++ b/extern/vgsound_emu-modified/vgsound_emu/src/es550x/es5506.hpp
@@ -35,7 +35,7 @@ class es5506_core : public es550x_shared_core
 
 				inline s32 clamp20(s32 in) { return clamp(in, -0x80000, 0x7ffff); }
 
-				inline void clamp20(output_t src)
+				inline void clamp20(output_t &src)
 				{
 					m_left	= clamp20(src.left());
 					m_right = clamp20(src.right());
@@ -76,7 +76,7 @@ class es5506_core : public es550x_shared_core
 					return *this;
 				}
 
-				output_t &operator=(output_t src)
+				output_t &operator=(output_t &src)
 				{
 					clamp20(src);
 					return *this;