Plug the speaker jack into the notebook not-quite-all-the-way?

I was recently working on some mixing and editing for the album I'm producing. I was using headphones. I was working on panning the overhead mics for the drum tracks left and right, and couldn't understand why they weren't moving in the stereo field, but rather just seemed to phase a bit funny. There are billion different ways to modify and route the audio within the software, and I'd just been doing a bunch of tweaking, and I was sure I'd made some kind of a mistake when moving the drums onto their own virtual bus. I spent quite a while trying to find my mistake, before discovering that the Radio Shack female-female jack that I was using to plug my headphones into the extension cord needed a bit of extra pressure to snick all the way into place.