Clicking noise sony bravia kdl-40v3000

Question

My new Sony Bravia kdl-40v3000 lcd hdtv is making a clicking/crackling noise when it is powered off.  It lastes for about one to two minutes.  Is this normal?  Do you know what it is?  I had returned my first tv after about ten days because of this.  Only to find that the replacement tv is doing the same thing.   Any help is much appreciated.  Thank you for your time.  Marinabravia after one making a clicking/crackling noise