diff --git a/nyxlabels/update_trx_with_labels.m b/nyxlabels/update_trx_with_labels.m
index b7fcbf62373ce0292fe5cd87010082c7a810e4e3..10ecd71d1007b536f7c290006f3a28f7218a2d3a 100644
--- a/nyxlabels/update_trx_with_labels.m
+++ b/nyxlabels/update_trx_with_labels.m
@@ -80,7 +80,7 @@ end
 
 if isfield(args, "outputfile")
     trx = updated_trx;
-    save(args.outputfile, "trx");
+    save(args.outputfile, "trx", "-v7.3");
 end
 
 function label = map_label(args, label)