I can't seem to get my iPhone 4s to drive video to my Insignia tv.

I can't seem to get my iPhone 4s to drive video to my Insignia tv.

I've tried connecting it both via the HDMI Digital AV Adapter and the VGA adapter, but in neither case does either the phone or the TV seem to react.

In both cases the TV complains that nothing's connected, and the phone dosen't react regardless of when either adapter is plugged in.

Is there some special setting hidden somewhere to turn on mirroring? Some sort of driver issue with this brand of TV?

It's rather awkward to troubleshoot things that should be as simple as plugging it in.