something similar to this happened in my RX8. I put LED bulbs in the parking lights located beside the headlights and after about 2 weeks the passenger bulb started blinking as you described 1 second intervals and wasn't "flickering" so I took it out and a few days later the driver side went really really dim so I gave up and figured it was some crappy bulbs and put the old bulbs in and never thought about it again. Strange that almost the same thing has happened with yours.