diff --git a/aegisub/src/mkv_wrap.cpp b/aegisub/src/mkv_wrap.cpp
index 12dec661b31f46706b6ee4e14e9c3216b5aae5ba..c9200775fea41fa3293e4ef185c19119958d8f16 100644
--- a/aegisub/src/mkv_wrap.cpp
+++ b/aegisub/src/mkv_wrap.cpp
@@ -120,7 +120,7 @@ static void read_subtitles(agi::ProgressSink *ps, MatroskaFile *file, MkvStdIO *
 		}
 		// Process SRT
 		else {
-			blockString = wxString::Format("Dialogue: 0,%s,%s,%s", subStart.GetASSFormated(), subEnd.GetASSFormated(), blockString);
+			blockString = wxString::Format("Dialogue: 0,%s,%s,Default,,0,0,0,,%s", subStart.GetASSFormated(), subEnd.GetASSFormated(), blockString);
 			blockString.Replace("\r\n","\\N");
 			blockString.Replace("\r","\\N");
 			blockString.Replace("\n","\\N");