That is normal, mine does the same thing and I have the same setup. You really shouldn't leave your car on and turn off your radio. If you did someone could be on the same channel as you are and have your car take off from your pit space while you are out marshalling.
There is great need for a sarcasm font.
You never know when it will strike, but there comes a moment at work when you know that you just aren't going to do anything productive for the rest of the day.
Sometimes I post just to look at my avatar.