How do I troubleshoot S-Video + audio jack output not working in Ubuntu? [closed]

Question

Possible Duplicate:
How do I troubleshoot S-Video + audio jack output not working?

I connect my laptop to my TV using S-Video + audio jack. This worked perfectly in Ubuntu 10.10 but has stopped working in Ubuntu 11.04. I have tried switching from Ubuntu (Unity) to Ubuntu (No effects) and Ubuntu Classic, but it still doesn't work.

Ubuntu recognises that a second monitor is attached and picks the correct resolution. The TV screen remains blue as though there is no signal. The audio doesn't come through either. I have checked the cables are plugged in correctly, and the connection into the TV works (replacing the laptop with a DVD player works).

I am using an Intel graphics card, not NVIDIA.

Any suggestions on further troubleshooting steps?

Answer 1

Duplicating my AskUbuntu answer:

If you don't know what your graphics card is, type lspci in the terminal. You should see one of Intel, ATI or NVIDIA in the output.

Using your favourite search engine, find others with the same problem as you who are using the same family of video card. Find a workaround if there is one, or subscribe to the bug and hope for the best.

I've found references to S-Video problems across many releases of Ubuntu. Prevention is better than cure, so next time I'm testing from a Live CD before upgrading.