At first it waits the full 18 seconds before continuing, but over time the wait time gets shorter, after an hour or so it is down to only waiting 8 seconds and after a day or two it is not waiting at all. If I restart my app then all is back to normal. I check and there is no activity on the port.
Thanks so much, although I am pretty positive there is no activity on the port, since it degrades over time. But in any case I have implemented a timer like you suggest to guarantee the right amount of "wait time"