Hello - I have two identical clips of the same video/audio. However, one version is slightly faster than the other (it was initially PAL formatted at 25 fps), resulting in video/audio being slightly sped up. How do I slow down the faster clip to match the original master?

They need to be synchronized perfectly.

I would still like to have the ability to keep both audio tracks (the master and fixed-faster version) separate from one another.

Currently using Final Cut Pro X 10.2.3.