i've had to do this in ableton (for some reason my audio seems to hang a little to the right on my computer). i'd recommend that if you have it, or basically anything where you can pan WHILE you listen to it, and be able to look at the volume levels for each channel, to make sure they're even.

Audacity should be able to do this. If it doesn't have a discrete panning setting you can bounce the audio tracks to split mono and increase the gain of the right channel to match the left.

Make sure that they're actually panned and that it's not just your headphones or ears being wacky. I don't know about Audacity, but I know GoldWave (shareware) displays a stereo file as L and R and has summing tools, which will help you compare and find the exact gain discrepancy (if any).

How can one do this? Which programs have to ability to fix this?

Basically I have a whole batch of old recordings that sounds slightly panned towards the left headphone. It"s not major but it gets annoying after a while to listen to. An obvious solution would be just to re-record but unfortunately these songs have all been erased from my LSDJ cart.

I want to simply try and even out the panning with another program. How can one do this?

Thanks in advance.