From your description of the problem, it sounds as if your text has it's own background. To eliminate the background, select the magic wand mask tool on the left side of the screen. Click on the background to select it, adjust tolerance as necessary, and hit CTRL-X to cut. If your text includes an A or P, you will need to repeat the process to remove the white inside the letters. If this process leaves your text a little jaggy, just use the feather tool in effects/object menu. you may also wish to use AA's assistant in conjunction with the feather tool for a cleaner result. I hope this helps.