diff --git a/aegisub/src/auto4_lua_scriptreader.cpp b/aegisub/src/auto4_lua_scriptreader.cpp
index e7fcf0b38..3206df6fe 100644
--- a/aegisub/src/auto4_lua_scriptreader.cpp
+++ b/aegisub/src/auto4_lua_scriptreader.cpp
@@ -50,6 +50,8 @@ namespace Automation4 {
 		size_t out_bytes = sizeof(buf);
 
 		conv->Convert(&in, &in_bytes, &out, &out_bytes);
+		if (in_bytes > 0 && in != in_buf)
+			file.seekg(-(std::streamoff)in_bytes, std::ios_base::cur);
 		*bytes_read = out - buf;
 
 		// Skip the bom