Putting in a bigger fuse won't help. Unless you have skill in electronics you will have to find someone to fix it. The amps I have worked on all had blown output stages (transistors or modules). But it could technically be anything. I wouldn't think a "leaky" cap would cause total failure of the channel. Does a leaky cap look different than a normal one? I have never seen a cap actually leak anything except ones that exploded...

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1998 C230 330,000 miles (currently dead of second failed EIS, yours will fail too, turning you into the dealer's personal human cash machine)
1988 F150 144,000 miles (leaks all the colors of the rainbow)
Previous stars: 1981 Brava 210,000 miles, 1978 128 150,000 miles, 1977 B200 Van 175,000 miles, 1972 Vega (great, if rusty, car), 1972 Celica, 1986.5 Supra