A3 wrong GPS speed

ap0stol

Hello from Russia.
I badly understand Chinese, so I write in English.

Hope you can help me.

In my A3 i have a bug (problem) with GPS speed.
My metric units for speed is kilometre per hours (km per hour).
GPS found sattelites and locate my position and speed.
But A3 have a bug with speed.

I.E.
If i drive with speed more than 50-60 km per hour - all fine. A3 shows real speed.
If i drive with speed less than 50-60 km per hour - A3 doubles my speed and tell me that i drive with Speed 80 km per hour (if i drive 40 km per hour) or 70 km per hour (if i drive 35 km per hour)

Any suggestion?
Thx