You can help your GO understand what you are saying by following these tips:
Mount your GO about an arm's length in front of you, away from speakers or air vents.
Reduce background noise such as voices or the radio. If there is excessive road noise, you may need to speak in the direction of the microphone.
Speak fluently and naturally as though speaking to a friend.
When saying an address, try not to pause between parts of the address or add extra words.
Say "number one" or "number two" and not "one " or "two" when selecting an item from a list such as a house number.
Try not to correct mistakes, for example "Number four, oh I mean number five".
Important: Voice control on your GO is specifically for native speakers of the selected language who have a neutral accent. If you have a strong local or foreign accent, voice control may not understand everything that you say.