No idea at all, but if I had the problem I would test or replace the fobs battery.
Have you got access to Nanocom?
if you have sunroof leak the most obvious is that the roof receiver is gone... let's hope the alarm is set to ''always disarm with key'' or you can end up immobilised... get new(or known good) receiver asap, it's plug and play
I agree with sierrafery . Damp / condensation is a real killer to the remote receiver in the roof it's just to the passenger side in front of rear sunroof . Easy to get to . I took mine out opened it up and popped a little silica packet in after mine started playing up on damp days been fine every since . But I do now carry a spare just in case £50ish from LR