G5 focusing constantly - is this normal?

I just got a Lumix G5 and it's fantastic, but oddly it is always trying to focus, regardless of the various focus settings I select in the menu. The only way to make it stop is to put it in manual focus (MF). If I put it down on the table, for example, and it is has nothing to focus on it will try to focus continuously until it goes to sleep. I don't recall my GX1 doing this and wonder if this is normal. Seems like it would drain the battery quicker than necessary. I put it on 1 minute sleep to save battery. Has anyone seen this on other G cameras?