So my device shows wrong speed. i think shows meter per sec. I make factory reset then i install gps test or any gps app.i bought sygic full version but no luck, speed showing wrong. if i drive about 10hm/h shows about 32km/h. But location shows in real time correct. I try upgrade firmware from philips support site and no luck.
error i try both firmwares.
My device info

Maybe is some nmea update to change speed units to km/h ?
sorry for my bad english.