Please post your install method. This would be quite possibly the "problem". Another possibility is the soft phone you are using (if the call is terminating at the agent side) or the carrier you are using (if the call is terminating from the prospect side).
Also: describe what you mean by "the calls are dropping" ... are you saying they are on hold for 700 seconds and at that point the system "drops" them? or that an inbound call reaches an agent but is terminated by Vicidial at 700 seconds?
Asterisk Command Line output from an example call would also be appropriate (preferably after hours with no other calls on the system, controlled environment with no "extraneous" output ... we don't need to see 3000 lines of irrelevant code ... right?