I'm not sure exactly what was causing the problems but apparently on some early units weren't centering properly. All recalls should be located on the Spektrum community site located here.
http://www.spektrumrc.com/ You will have to create a login if you don't already have one. This is where you get updates for the DX8 as well as some "prebuilt" setups for certain models.
Go to the "Support" drop down and click on "Product Bulletins" for recall information on various Spektrum products.
Login to the "Community" to get updates or model presets.