My iPod® is playing, but there is no audio coming from the SoundDock®.
If you’ve just completed an operating system update on your iPod® or iPhone®, you may need to wait several minutes before using it with your SoundDock® system. In some cases, even though you’ve completed the operating system update, some of the apps on your Apple® device may require additional time to finish updating. Undock your Apple® device from the SoundDock® system for several minutes, then re-dock it. Make sure it’s properly seated in the dock
If your iPod® is in a case or protective sleeve, it may not seat properly within the dock. Removing the case or sleeve will allow the iPod® to fit in the dock, using the supplied insert
Try resetting the iPod®. The iPod® may have malfunctioned and might need to be reset. Refer to Apple® support for further assistance
Try resetting the SoundDock® system. Unplug the system from the power for 60 seconds. Remove the battery. Plug the system in without the battery, and see if the audio returns