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Recently my galaxy s4 headphone jack has been mistaken fried because I plugged in a 3.5 jack that was filled with electricity (thanks to the crappy speaker) So right now when I plugged in my headphone, the sound from left channel would crackle a lot, and the right channel doesn’t even play. The speaker still works, and I can still play the music just fine from the bluetooth. I’ve look up ifixit to replace the jack, and found across a similar person who have the similar problem but unfortunately he can’t solve the problem by replacing the headset. Anyway I can try to fix it? Thanks in advance.
If a replacement headphone jack does not solve your issues, there could be possible board damage caused by the shock. You’ll have to disassemble your device and check the board under a scope if you can. Look for burn marks or fried coils/fuses. Good luck!