I have an old uniden wx100 weather radio that works well, the function I like the most is after the voice has read the weather alert, it goes back to mute. fully automatic operation. My question is alot of the new weather radios have the voice set at a 5 minute run time before they shut off, sometimes annoying to hear 3-4 minutes of wx broadcast when alert has been over, Why is that? Are there any that do not do this?