i need a help with my sony tv

hello,

 i am new here. i have sony KN-32XBR400 TV. and i have been having problemm with picture. when i turn on the sound is coming but picture part. so i have to try some time until it get picture. but after i get picture working perfectly fine. and when i turn off at night and next morning when i turn on same process. so please please someone help me. i really apriciate

THANK YOU VERY MUCH