You dont need schematics, your fault is dry joints on the vertical chip. You probably are going to keep using it till the chip dies so be prepaired to buy a new one. At the moment you can open the set and find the vertical chip, Its a flat chip mounted on a flat piece of aluminium near the high vo;tage transformer. Check http://www.datasheetcatalog.org/datasheet/philips/TDA3654.pdf
you will find what it looks like though there are multiple variation. It will be a TDA or an LA, or uPC or if Sharp make it XO. Whilst you are in there with a soldering iron, remove the electrolytics and renew as found.