Dynamic text scrolling

I have a text box and I want the text to scroll one way then back again (like the song name on my iPod) so that the user sees all the text. I designed it and it works fine, but I have the background black and the text white and when it is scrolling the text background turns white so you can’t see the text. If I have it on a white background with black text it works fine. The textfield is named nowplaying and here is my code to scroll it:

scrollspeed = 50;
_root.onEnterFrame = function() {
 if (go) {
  if (0 == nowplaying.hscroll) {
   go = false;
  } else {
   nowplaying.hscroll -= scrollspeed;
 } else {
  if (nowplaying.maxhscroll == nowplaying.hscroll) {
   go = true;
  } else {
   nowplaying.hscroll += scrollspeed;

Any ideas?