It's been so long ago that I've even forgotten I've posted this question!
Thanks 4 answering, but I've already found the answer...using the default in-game commands.
NOTE; that F1 2016 actually recognizes your comands! (the commands marked in green!) So, for all commands u can use them to talk...without using voice attack! (finally voice recognition in games!)
Anyway, I'll show you a few examples of how I've edited voice attack coommands, because I can't remember ALL the voice commands in the game...! (who does??) Especially if some commands sound the same, so I made some of my own such as: fuel status, fuel update, weather report, weather update and so on
Here's the example of one such command, which I had trouble with:
Box This Lap - Press V key and hold for 0,05 seconds and release
Pause 0,3 seconds
Press RIGHT key and hold for 0,05 seconds and release
Car Status - Press V key and hold for 0,05 seconds and release
Press Right key and hold for 0,05 seconds and release (yep, no pause here!)
Press DOWN key and hold for 0,05 seconds and release
Pause 0,3 seconds
Press DOWN key and hold for 0,05 seconds and release
Pause 0,3 seconds
Press DOWN key and hold for 0,05 seconds and release
Pause 0,3 seconds
Press DOWN key and hold for 0,05 seconds and release
Pause 0,3 seconds
Press DOWN key and hold for 0,05 seconds and release
Pause 0,3 seconds
Press DOWN key and hold for 0,05 seconds and release
Pause 0,3 seconds
Press RIGHT key and hold for 0,05 seconds and release
Press D key and hold for 1 second and release
After testing them extensively..I can confirm the voice commands now work in both singleplayer and multiplayer.