When we test drove ours at the dealer, we had the sales rep take it back to the service department because of that noise. She came right back and said that he said it was the fuel injectors. Then I remembered the discussions on the forum - OH - that noise!
I consider a lot of this stuff like my Neptune washer. It makes a lot of strange noises I've never heard from a washing machine, but it's all perfectly normal for it. Come to think of it, that sounds a lot like my husband!