I see 2 possibilities here right away. Common to all tv sold by Philips. First, if it is reduced a little it is likely that it is an electrolytic capacitor. These components are filled with an electrolyte and the heat dries them out. They fail as a result. In the same circuit are a couple of low ohm value resitors that change value due to the heat. After that, the vertical output IC may be failing or even gotten so hot it has corrupted the silder that connects it to the circuit. None of this is major.

Here is a link that might be useful: Electronic Repair & Schematics