diff --git a/source/ps/FilePacker.cpp b/source/ps/FilePacker.cpp
index 295d5585b3..b8fdfd9de4 100644
--- a/source/ps/FilePacker.cpp
+++ b/source/ps/FilePacker.cpp
@@ -33,7 +33,7 @@ CFilePacker::CFilePacker(u32 version, const char magicstr[4])
 // Write: write out to file all packed data added so far
 void CFilePacker::Write(const VfsPath& filename)
 {
-	const u32 size_le = to_le32(u32_from_larger(m_writeBuffer.Size()));
+	const u32 size_le = to_le32(u32_from_larger(m_writeBuffer.Size() - 12));
 	m_writeBuffer.Overwrite(&size_le, sizeof(size_le), 8);
 
 	// write out all data (including header)