diff --git a/aegisub/src/ffmpegsource_common.h b/aegisub/src/ffmpegsource_common.h
index 6eaea5333..992b669cc 100644
--- a/aegisub/src/ffmpegsource_common.h
+++ b/aegisub/src/ffmpegsource_common.h
@@ -45,8 +45,8 @@
 #include "dialog_progress.h"
 
 
-#define FFMS_TRACKMASK_ALL		0
-#define FFMS_TRACKMASK_NONE		-1
+#define FFMS_TRACKMASK_ALL		-1
+#define FFMS_TRACKMASK_NONE		0
 
 
 class FFmpegSourceProvider {