Creaking Noise -Look Keo Sprint

I have fairly new (300 miles) look keo sprint pedals. I notice a creaking noise in the left pedal especially if I need to put pressure going up a hill or standing. You can also hear it a bit if you shift your foot left and right but don't eject from the pedal. Doing NYCTri next week so just wondering if I should be worried or if there is a recommended lube for the pedal.