Maps spoken voice directinos on my iPhone 5 iOS 6.0.1 sometimes works

My iPhone 5 with iOS 6.0.1 has a problem with Maps turn-by-turn spoken instructions. It apears to work when first starting on a route, but ceases before the destination is reached.

Today I noticed that in some parts of the Miami (FL) area the screen attempts to synthecise what nearby structurest. At best they are not an accurate depiction. At worst is is very distracting. I hope there will be an option to supress these pseudo-landmark distractions.

Thanks