Lens fog

It should have desiccant bags inside. You can purchase and add them.
When you open them up, make sure you do it in an environment that has below 50% humidity levels. Not outdoors on the porch when it's raining. ;)

May I add that it is the absolute humidity, not the relative humidity, that is important when you seal the camera? Sealing the camera at 90 degrees F and 50% relative humidity is worse than sealing at 65 degrees F and 70% humidity. If you seal it up on a warm day with moderate humidity, the relative humidity inside will rise as the camera cools, and it will fog -- unless you use a desiccant pack to capture the remaining moisture.
 
Nonsense there is no need to add or replace silica packets on a camera that is not defective or improperly mounted... theses things don't need yearly maintenance..