James -
What's the distance between the smart jack, the CSU and your box? What kind of cables? I ran into some weird issues that seemed like timing, but turned out to be cable length, posted here:
https://www.sundance-communications.com/forum/ultimatebb.php?/ubb/get_topic/f/17/t/000208.html I've got issues with Airespring not publishing the right routing information, but never had any issues with dropped calls. The people who can't call us say they get busies, (some report fast and some report slow) or operator intercepts. Airespring pins it on us to tell them which carriers can't call us, but that's an impossible task, of course.
