Swirl marks on bottom of new CD's? Please help!

I bought a few new CD's at Future Shop the other day, and I noticed that a bunch of the on the underside have very very faint swirl marks, they almost look like water marks or something and it is not on the surface but under neath the plastic. Is this normal? I returned them both today only to find the 2 new ones I exchanged them for have the same swirl marks.

Like I said, it can only be in certain light, but if this will in any way, at any time compromise the quality of the audio on these CD's I want to return them until I get a good one.

Can anyone chime in here? I would greatly appreciate any help or experiences you guys have with this.

Thanks very much!!