I've bought another device to do this. A Blustream embeddder/de-embedder. Slightly more expensive, larger and is mains powered so yet another wall wart to find a home for. Digital and analogue audio out, but only analogue in. It has a load of DIL switches for various video signals, but worked on the default settings. Just as well, as the instructions talk about signals I've never heard of, and there are 16 choices.