When we 換片, we do not change right away, we open 片片, we do a sound "shu shu...." and baby loves to vv when we open a 片片, normally my baby will vv when we make the "shu..shu.." sound. Then we can 換片 and no need to worry he vv again.
But it takes time to change and you need to repeat this every time when 換片.