Bought this brand new one week ago. Have taken about 30 shots with it. This morning I was going to use it and noticed the insides feel loose. Not a like a screw or something like that but the whole thing. If I hold it in a vertical position and even gently shake it back and forth I can hear it and feel it. I have other lens that have a small amount of play but this one seems excessive. Does anyone else have this lens and does it exhibit the same "play" as mine? Do you think this is normal and just the nature of the build? Thank you, Larry.