Thread: Noise from speakers when pc connected to tv?

I wasn't sure what forum to post this in but I tried out my car pc on my tv using the tv out and it works but i get a hum from the speakers. It happens when I plug in the s-video cable into the tv. I thought it was strange but I know pcs are a noisy environment and it's possibly amplifying noise from the power supply through the vid cable. I dunno. Any clues?