Is there a dock with optical audio or co-ax out ?

I want an optical audio out or even a co axial out for sound in fact So as to hook to an av system rather than using analog pins?

I presume ipod docking stations will also take an iphone 4 or an ipad?

Pardon my ignorance on these matters!

If there is, whats the ballpark price and where would you get one?

Thank you

Gregor Samsa

First result of a google search for "iPod optical dock" is

http://www.macworld.com/article/134107/2008/06/wadia.html

Don't know anything about it, but it might be a good place to start your search.

As for dock/idevice compatibility, newer iPods/iPhones & ipads won't charge on older docks, due to a change Apple made to the pin configurations when they dropped support for FireWire. So check for product compatibility.

Also, iPads won't physically fit in iPod/iphone docks. But you can get an extension cable to use them. There was a thread aboutit here recently.