headphone jack crackling static

I recently used a 3.5mm plug with RCA connectors on the other end of the cable to hook my phone up to an old stereo console aux of which I thought that's what it was. After doing that the headphone jack output has nothing but a popping crackling sound with very little music coming to it when using regular headphones. At full volume it completely disappears. Did I ruin the jack or short something out attached to it? everything else works flawless thru the phone speaker.