Charger that lets you use an iPod Touch while charging? Are there any chargers that let you use an iPod Touch while it's being charged?

I have a simple wall charger, but it disables the iPod's audio while it's plugged in.  I can plug the iPod into a laptop, but that seems a bit inconvenient and inefficient.  I even tried using a clock with a built-in iPod dock, but the clock always tries to start playing iPod music whenever the iPod is plugged in and also tries to disable the iPod's built-in speakers.
I have an Apple USB Power Adapter that came with my iPhone and in no way does it prevent me from using any feature of my device while charging. I can play audio out of the built-in speaker as well as through the headphone jack without issue. I'm not sure what wall charger you have, but if it's the Apple USB Power Adapter you should try to return it or exchange it as yours is likely defective.