voice cutting off half way through an instruction

When approaching a junction etc. Serena starts to tell me which way to turn etc which cuts off before completing the instruction but she gives me the full instruction when I am on top of the junction. How do I change the system to get the full instruction in good time to make the move. Also, I have just bought the 2015 full european maps and installed them successfully I would put them on the forum if I knew how to do it perhaps someone can enlighten me. I am very pleased with primo and use a download from GPSworld for radar up-dates the only thing that bugs me is the instructions which are not complete as I approach a junction If I could get this right it would be a perfect Sat Nav. aggie

my voices seem to start late, like somtimes the start of the first word is missing, is there a fix for these problems?