Wow, ok. So here's a little more data. I am enamored with the Cessna Citation Longitude right now, so I've mostly been using that. When I switched over to the Beechcraft Baron G58, vPilot comms worked beautifully. When I switched back to the C700, I once again got no TX or RX on comms from vPilot. As you can see in my screenshot, I've got Com1 tuned to the active ARR/DEP at KLAX.
When in the Baron, I got the expected turquoise colored frequency color change on COM1 on vPilot, and both the RX and TX lights lit up as expected. As in the screen shot, I see no colored frequency for COM1