I installed a Partner ACS R8.0 with small voice mail card and 308EC expansion module. The client has a published CO line which rolls to two lines in hunt for his commercial business, a private residential line programmed as line 4, which rings only in the residence and at his extension, and a toll-free number, provided by a different vendor, that forwards to the published line.

The problem is intermittent in that some inbound calls - the client is unable to provide a ratio - leave the employees unable to hear the callers but the callers can hear the employees. This was occurring on one occasion, while I was on-site training on the system, so I had the employees instruct the callers to please call back. When the callers phoned in again, I instructed the employees to apologize for the inconvenience and to ask on what number the callers dialed in; invariably it was the toll-free number.

I am inclined to believe that the problem is at the SO, so I have opened trouble tickets with the toll-free carrier, but to no avail. Is there perhaps something I overlooked in trouble-shooting locally? As I said above, the toll-free number is being forwarded at the remote SO?

Thank you, in advance, for any ideas on how to resolve this issue.

PS: The reason the 800 number was forwarded remotely, I presume, is because their old ad-hoc system was jury-rigged beyond capacity. I suspect that bringing the circuit to the premise will cure this problem, but I want to have a measure of certainty that I am advising the right course prior to making the request.