Is My Headset Broken?

I use a steelseries headset that i use on a daily basis. But it recently started to screw up. I also use a Jack extention (i plug it into the back where the Headphones would normally plug in then plug the headphones into the end of that) A little awhile ago i realized only the right side was recieving audio so then i go into the back and plug it all the way in and its fixed. now a little while later when i go onto the computer to watch someone play a game on youtube whenever the headphones are

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