I have two rips of the three-hour extended cut of Avatar on my computer. One is 360p DVD rip, not fantastic quality, and has great surround sound audio. The other is a 1080p Blu ray rip, a little ugly compression but otherwise fine, but with crappy mono audio. Can I separate the audio track from the DVD version and apply it to the Blu-ray? It gets more complicated: the DVD rip is in two parts.