Felix's helmet heating apears to be broken. They've also cut the radio talk between Felix and Joseph.
(edit: the feed cutting was probably just me, just saying it was an unfortunate time for it to do so)
edit 2: They just said that the problem is specifically for the visor (to prevent fogging and icing), not the whole helmet... They still haven't found out what's wrong.
Visor heat are the wires in the glass that keep it from fogging, like the rear defroster in your car.
And it seems they're not sure if the heat is broken, or just the thermometer.