The problem is this style block:
#newsletter_textone {
bottom: 255px;
color: #ffffff;
display: block;
font-family: arial,helvetica,sans-serif;
font-size: 14px;
font-style: italic;
margin-left: 574px;
position: relative;
}Specifically, this line: bottom: 255px;. The relative positioning is changing upon signup because the signup form disappears upon signup, hence changing the relative distance/spacing in the area.