diff --git a/src/audio/audio.cpp b/src/audio/audio.cpp
index 5366fc03..139b3acf 100644
--- a/src/audio/audio.cpp
+++ b/src/audio/audio.cpp
@@ -608,6 +608,7 @@ void Audio::reset()
 
 Audio::~Audio() { delete p; }
 
+#ifdef MKXPZ_RETRO
 bool Audio::sandbox_serialize(void *&data, mkxp_sandbox::wasm_size_t &max_size)
 {
 	if (!mkxp_sandbox::sandbox_serialize((mkxp_sandbox::wasm_size_t)p->bgmTracks.size(), data, max_size)) return false;
@@ -645,3 +646,4 @@ bool Audio::sandbox_deserialize(const void *&data, mkxp_sandbox::wasm_size_t &ma
 
 	return true;
 }
+#endif // MKXPZ_RETRO
diff --git a/src/audio/audiostream.cpp b/src/audio/audiostream.cpp
index 379cbe80..d1ddc5d5 100644
--- a/src/audio/audiostream.cpp
+++ b/src/audio/audiostream.cpp
@@ -460,6 +460,7 @@ bool AudioStream::sandbox_serialize(void *&data, mkxp_sandbox::wasm_size_t &max_
 bool AudioStream::sandbox_deserialize(const void *&data, mkxp_sandbox::wasm_size_t &max_size)
 {
 	AudioMutexGuard guard(mutex);
+
 	{
 		std::string value;
 		if (!mkxp_sandbox::sandbox_deserialize(current.filename, data, max_size)) return false;
diff --git a/src/audio/soundemitter.cpp b/src/audio/soundemitter.cpp
index bfc00f84..dd39ed3f 100644
--- a/src/audio/soundemitter.cpp
+++ b/src/audio/soundemitter.cpp
@@ -341,6 +341,7 @@ SoundBuffer *SoundEmitter::allocateBuffer(const std::string &filename)
 	}
 }
 
+#ifdef MKXPZ_RETRO
 bool SoundEmitter::sandbox_serialize(void *&data, mkxp_sandbox::wasm_size_t &max_size)
 {
 	if (!mkxp_sandbox::sandbox_serialize((mkxp_sandbox::wasm_size_t)srcCount, data, max_size)) return false;
@@ -443,3 +444,4 @@ bool SoundEmitter::sandbox_deserialize(const void *&data, mkxp_sandbox::wasm_siz
 
 	return true;
 }
+#endif // MKXPZ_RETRO