for some unknown (to me anyway) reason my interior light has just started f****ing up.
When I open the doors, the lights sometimes come on, other times, the light wont come at all, once the door is shut, it then comes on? wtf?

Its not just one door either, its all of em, just randomly happens.

any ideas?

Check the door light catches as one may be playing up, or the wires in the roof light may be shorting out.

are the door light catches wired in series?

IE if one is playing up will all play up?

If one doesn't work, then the rest won't work. It has happened on my dad's NC and a mate's EB sedan. Check the door buttons and see if the wires are intact. Then check the roof light.