OEM incandescent license plate bulbs singed the socket!

I've got similar singe marks, but just on one side of both bulb holders. I also had intermittent lights being on/off when they should be on.

From taking things out and testing, I think the problem is with the electrical contact between the bulbs and the bulb holders. Could be a corrosive layer adding some resistance. I also bent the copper contacts in the bulb holder out to make better contact when reinstalled. I also will buy new bulbs and replace them. The poor electrical contact would explain both the intermittent on/off and also the singe marks - the resistance at that contact will generate heat.

I will replace with regular incandescent bulbs, not wanting any electrical issues. But from looking at the LED options, I see that their electrical contacts are MUCH better, and that feature alone would be the most important for me. The LED bulbs have 4 flat surfaces to contact the 4 copper prongs on the bulb holder. (4, but only one of each pair needs to make contact). Vs, the incandescent bulbs just have little doubled over wires with no redundancy - 2 wires for 2 contacts.

BTW, another "root cause" type issue for problems with these license plate bulbs, I think, is that they are about the same shape, in about the same location, and with about the same compliance as the hatch release button (at least on my 2012 v). I have found myself a few times, in my brief ownership so far, pressing on a license plate light lens and wondering why the hatch is not opening. Obviously it is easy enough to know that the hatch release is centered left to right, but ...