Thanks to @sarmatios , I repaired my N64 too.
I removed the chip and bridged the connections and had still no sound. The only thing that worked for me was a wire from pin 7 to the output port like he said. But you have to connect pin 8 of U2 to the port too or you will get just mono. Pin 7 is for the right audio channel so it should connect to pin 12 of the multi out and pin 8 of U2 to pin 11 for the left audio channel.
I have no clue whats actually broken. The capacitors are fine. Maybe the resistors R57 and R58 on the back.
Anyways, thanks a lot guys.
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