As the title says. When I plug into the headphone jack, the audio sounds awful. If I'm listening to a song, the background music will be there and sound half decent (not great though) but the vocals will be barely audible, and they sound as if they are underwater.
Do the headphones definitely work fine when plugged in to something else?
It sounds to me as though the ground connection between your headphones and the jack socket in the headset isn't connected. This will give you the difference between both channels out of both sides leading to a budget vocals-removed karaoke sound.
Try wiggling the plug in the socket or plugging it in and unplugging it several times as it may just be a dirty contact. If the headphones definitely work and this doesn't fix it, I suspect a dodgy jack socket on the headset.
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Yeah, I've been using these headphones for the past few months on the pc itself with no issues. I've also tried different headsets all with the same issue. Does seem to be a headset issue unfortunately.