I have the same equipment and can't do it either I'm afraid.
On a slightly different subject does your set-up give you (auto) DTS 5.1 surround on the relevant Sky Movie channels? Mine only continues in Neo 5.1 which is how I listen to all the Sky+ channels. I use an optical cable to link to the Receiver but would expect the mode to change to DTS if watching relevant movies on Sky? Any ideas?