diff --git a/Units/MMLAddon/mmlpsthread.pas b/Units/MMLAddon/mmlpsthread.pas
index d8dfc7d..8b32a7c 100644
--- a/Units/MMLAddon/mmlpsthread.pas
+++ b/Units/MMLAddon/mmlpsthread.pas
@@ -288,7 +288,7 @@ end;
 
 procedure ps_DebugLn(str : string); extdecl;
 begin
-  if CurrThread.Prop.WriteTimeStamp then
+  if Assigned(CurrThread) and CurrThread.Prop.WriteTimeStamp then
     str := format('[%s]: %s', [TimeToStr(TimeStampToDateTime(MSecsToTimeStamp(GetTickCount - CurrThread.StartTime))), str]);
   mDebugLn(str);
 end;