I want to combine 2 files to use as Intoduction Media on all of our company's discs, but I can't figure out a good way to do it. The problem is with the AC3 audio. Our company's flying logo screen is 25 seconds long, and uses 5.1 AC3 audio. I want to put a Dolby Digital logo file (approximately 30 seconds, also 5.1 AC3) behind it, so that when the disc is inserted, our logo will play, foloowed by the Dolby logo, and then go to the menu. Normally, I would just put both files in Vegas and render them to one, but since you can't input AC3 into Vegas, I don't know what to do. I want to preserve the 5.1 effects, so I can't just downmix to PCM Stereo.