FrSky G-RX8 issues
 

Could anyone tell me what is the problem?
I flashed my G-RX8 for firmware 12.29.2017 version. Now, Alti-v and Speed-v do not work on my X10S. After connecting the battery to the ESC (and G-RX8 gets the voltage), screen shows certain false alti and vario datas which are decreasing to zero in 3 sec.. But after, it does not work. Screen shows 0 meter and 0 m/s even if I move my receiver. I have already tried to push F/S button for more than 3 seconds. It probably changed altimeter function from enabled to disabled and back, but it has not helped. There are no voices indicating whether we rise or fall. I always connected my receiver correctly.
What can I do?
Steve