The GameGear's audio board has a few weak points: Not only can the capacitors leak, but the amplifier also dies sometimes and the small switch in the 3.5 mm port that switches between headphones and speakers slowly rots away.
But there is a remedy for this now: Just replace the audio board with a new one! New technology also means higher reliability and better sound.
The exchange is super easy: Unscrew the Game Gear, unplug and unscrew the old board, screw in the new one and plug it back in.
No soldering or other modification is necessary!
If you order the board together with a capacitor exchange or McWill display conversion from us, we will install it without further costs.