Not sure what you mean but I’ll take an alternate stab at it…
Vegas tends to put fade in / outs on audio regions. For example, if you split an existing region, there will be a small fade out on the end of region 1a, and a fade in on region 1b. You may need to zoom in to a max level to see this.
So, my point is that perhaps the audio is there, but you’ll need to zoom in and make sure there isn’t a slight fade in / out at each point where one slice meets the next.