Mind Boggling Headphone Jack Issue!

So, I replaced my power sensor cable and everything went fine. Put everything back together, phone worked fine so I went to bed thinking "this rocks! my power button finally works again."

Woke up in the morning and took a trip to the gym to get a workout in which I thought would be even better than it had been in months since I could now turn my screen off whenever I wanted to. So I go to start working out, plug my headphones in and press play. Here's where the mystery comes in...

When the headphones aren't plugged in, the phone plays audio perfectly, the volume controls function perfectly, and everything works great. Once the headphones are plugged in, things start acting buggy. the volume controls, whether using the buttons or controlling using the on-screen slider wont control the sound the way they should. when you turn the volume up all the way, the sound is blaring out of the headphones to the point where its about to blow the speakers. when you turn the volume down, the sound levels lower slightly until about the half way point then beyond that it doesn't ramp down. As you move the volume slider down to the lowest point, the sound just "clicks" off at the lowest point. Then, when you move the volume slider up a little, the sound will abruptly click on again. As you move the volume slider around, you will hear static, distortion, and sometimes the music will just cut off.

A couple things to mention. First, it's not the headphones. I verified by using the headphones on my girlfriends iphone and they sound fine. Also tried plugging my iphone into the aux jack in car and had the same issues. Second, the audio plays fine through the dock connector.

I decided to retrace my steps and tear the phone back down. My initial thoughts were a grounding issue. I was extremely careful with the ribbons during the power sensor replacement and I don't see any signs of damage whatsoever on the headphone/volume control ribbons nor the connectors.

At this point, I went through with rubbing alcohol and cleaned all metal contact points on the logic board and all connectors. Also checked to see that grounding clips were placed correctly and making contact where they should be. Everything seemed to be completely in order, no signs of stray dust or bad grounds. The headphone jack is clear inside and I have blown it out with air so the jack is not the issue. It has always worked fine up until the power sensor cable replacement.

Well, hopefully someone has some ideas. I have searched everywhere for this issue and have found some posts from people that had similar "headphone static" issues and the issue continued even after they replaced the headphone jack, cable and connector. The other people with this ongoing issue seem to never find an answer so I hoping some "Mac Genius" will know this one. Thank you for your time.