I guess, for me, I treat all of Pierogi as still being questionable. You may be getting 4m now, but maybe you could be getting 5m if I set things up just right... So yeah, I don't know exactly what you should treat as an issue and what you shouldn't. It is also true that many manufacturers set up their devices to be extremely tolerant of off-spec IR signals. (After all, most remote controls are constructed very cheaply.) I'm always amazed looking at the LIRC config files; some of the timings in them are off by more than 20 or 30 percent, and yet they still work fine.