Howdy Gang- I have an esi 600- which we love- however we have a polycom conference phone, that when we have a conference call (sometimes with 2, 3, 4) on the call- sometimes the phone will go to a fast busy- eveyone on the call hears the fast busy- when this happens, we hit the flash button- and it will go away for awhile- sometimes we have no issues, sometimes we have multiple.

Thoughts?