Does teh speaker cone move one direction and stay there? In other words is there DC on teh amp output? If yes to either, TURN IT OFF, you will melt your speaker - if not already done.
Work with NO speaker load until we know the amp is stable and not making DC.
The swollen C13 ought to be replaced, but it appears to just be the fan supply, so no audible difference.
Resistors never burn up on their own, something else takes them down. Usually a transistor. Especially if some of your power transistors are getting hot. They aer very suspect.