Problems connecting PS3 to TV

Hello,

I have a problem to connect my PS# to the TV- It worked before but the PS3 has been connected to a different TV and when I try to connect it again to the TV we normally use - I connect both HDMI cable and the cables (red,yellow,white). Then I need to choose a TV channel I want to use. When I choose the HDMI, ther is a sound, but no picture. If I choose channel 3, there is a picture but no sound. Can you help me /advise how I can resolve this to get both sound and picture?

Thanks a lot!