I just lost my video and I can't find my manual

Question

I have this dvd system and I was trying to hook up the sound and was changing setting when I hit something that I shoudlnt have and now I lost my picture and I can't get into the settings to change it back. Also I don't have my manual and I have been searching online to try and find a solution. Please help me by providing me with a reasonable solution. Thanks

Ps I know this thing sucks don't remind me, I just need help to get it working.