I'd lean more toward the ignition switch. It's a cheap, plastic part that causes all kinds of trouble. Electrical gremlins all over the place. Some of the problems caused by this that I've seen are key getting stuck in, key won't go in, key won't turn, A/C won't work, dash lights flashing, etc.
That's a cheapo part you can get at the local VW dealer if you need it now or go to your local auto parts store and have it in the next day or two for about $30. Some have found them as low as $10 on eBay.
The part number on the switches I bought is 4A0 905 849 B. I got three so I have them on hand in the future. Porsche does not carry the switch any more because they redesigned it and now they only replace the whole locking mechanism with the new switch.
Good luck!