I've been noticing lately that my pearls seem to have a habit of spinning around my neck during the day. It's particularly noticeable with shorter strands that have a definite center pearl like my blue-green strand or my multicolour strand. I'll be going along thinking things are fine...and then suddenly I'll catch a glimpse of myself and my center pearl is halfway up one side of my neck! Does anyone have any tips on how to prevent this?