Rotate screen?

[wingrunr21]

I have a mythtv box set up on a Via M10000 Mini-ITX mobo using the S-Video out (it also has RCA out) to hook it up to my TV. The problem is, the picture on the TV is rotated about 20 degrees counter-clockwise. When I say rotated, I mean that the entire rectangle for the image is more like a diamond now. Since my TV is an old CRT, is there any way to tell X to rotate the image 20 degrees clockwise?