diff --git a/Source/Core/DiscIO/Volume.h b/Source/Core/DiscIO/Volume.h
index d55a425d91..26c11e678c 100644
--- a/Source/Core/DiscIO/Volume.h
+++ b/Source/Core/DiscIO/Volume.h
@@ -114,7 +114,7 @@ protected:
 			return CP1252ToUTF8(string);
 	}
 
-	static std::map<IVolume::ELanguage, std::string> ReadWiiNames(std::vector<u8>& data);
+	static std::map<IVolume::ELanguage, std::string> ReadWiiNames(const std::vector<u8>& data);
 
 	static const size_t NUMBER_OF_LANGUAGES = 10;
 	static const size_t NAME_STRING_LENGTH = 42;
diff --git a/Source/Core/DiscIO/VolumeCommon.cpp b/Source/Core/DiscIO/VolumeCommon.cpp
index cb4386af68..f503e259ca 100644
--- a/Source/Core/DiscIO/VolumeCommon.cpp
+++ b/Source/Core/DiscIO/VolumeCommon.cpp
@@ -57,7 +57,7 @@ std::vector<u32> IVolume::GetBanner(int* width, int* height) const
 	return image_buffer;
 }
 
-std::map<IVolume::ELanguage, std::string> IVolume::ReadWiiNames(std::vector<u8>& data)
+std::map<IVolume::ELanguage, std::string> IVolume::ReadWiiNames(const std::vector<u8>& data)
 {
 	std::map<IVolume::ELanguage, std::string> names;
 	for (size_t i = 0; i < NUMBER_OF_LANGUAGES; ++i)