i have a tom tom XL model, i seem to be having problems with it regarding giving vocal directions, i.e. sometimes when you approach a junction usually it would say for instance 3rd exit off roundabout a123,on several occasions you just get the last digits i.e. 23. on other occasions when approaching an exit you could be on top of the exit before it speaks,then sometimes you dont get any instructions but the visual map is spot on. can anyone advise ? is it something i have done wrong ?or am i missing something. i never had any problems with my first tom tom. 