I suspect that you've put a wide-area trunked system into your Favorites List and are scanning it without location control. In that case, it will spend 1-2 seconds per enabled site to clear the trunked system. I recommend you set the FL to use location control and set your location.
Thanks for the advice, that did speed it up. If I was only monitoring sites in my area, and avoided all other sites, why does location control matter? I can definitely see the speed difference from 30 mile to 0 mile range, but I'm only monioring a few sites.