Hi Rick,
G711 phone calls take about 100k.
G729 (compressed) take about 40k.
Because your upload speed is 800k, that is your effective limit (there is no use being able to hear if you cannot speak, right).
Also, nobody ever gets what they bought speed wise.
So, if the connection was used FOR VOICE ONLY, you'd be OK up to 7 simultaneous phone calls at G711.
Obviously, if the connection is shared, the computers will hog as much bandwidth as possible without some form of traffic shaping or Qos.
I don't know how many phones you have or what your computer needs are so can't really say if 5/800 is enough or not.
One thing is for sure though, if you are experiencing lots of delay and packet loss, increasing the bandwidth will do NOTHING!
I have had success in the past taking the screenshot from pingplotter and email/showing it to the ISP if one of the hops looks bad.
Dave
