I doubt anything except a deck is sensitive to racking. Back in the days before cd was invented it was easy to justify a rack as everyone used a record deck. When cd came along and displaced turntables then suddenly the manufacturers had to claim that all electronic items are senstive to justify their continued existence and invoke garbled nonsense like components vibrating in the earths magnetic field and other such tripe. Mana work well for certain decks which work on the same principle - like pink triangle - but their worth is greatly over stated IMHO. The cheaper units are ok but much above that it becomes comic.