Thanks so much for the reply.

It is a shared T-1 that scales voice with data over 12 channels and 12 are reserved for data only. All main office phones are NOT IP.

We are only 12 people in the main office and the major source of internet traffic is RDP (terminal services) from remote users and from using gotoassist remote control software on and off by 2-3 users at the main office throughout the day.
Based on testing of bandwidth usage I dont believe that we are even coming close to using it all.

We are not using QOS, however they bypassed the router when the set up the IP card. All VOIP traffic is off my internal network. So I had considered QOS when I was researching myself, but since we bypassed the router there was no benefit.

The users all have different ISPs. They also all have different routers at home. We asked before we went live with this if it mattered and we were told "any router will do." The only reason that I didn't question this was because all 5 of these people had been using vonage for 2 years on the same equipment without incident. This is the biggest reason I think the problem is here.

I really appreciate you guys taking the time. I have been a long time lurker here and always find the answers I am looking for.