We have a reliable 10Mbps fiber connection and are using bandwidth.com sip trunking. We have two groups of users:
Group 1 uses polycom hardphones. They never report echo or other phone quality problems.
Group 2 is on an auto-dialer. They use Plantronics H261N USB headsets and spend their days in MeetMe conferences (it’s how the dialer patches calls through to them). Sometimes they report echo that is very faint and not bothersome, and other times it’s noticeable and annoying. The one guy I spoke to said it would last for the duration of the call and be gone on the next one. It might happen a couple of times per day to any one particular user. The echo they hear is always their own voice and I can’t hear the echo in recordings I am making of the calls.
It is possible that people on headsets are just on the phone more often, but we have a could of polycom users that are basically on the phones all day, and they report no problems.
Anyway, I can’t figure out a solution to the problem. It seems like the endpoint echo-cancellation of the softphones isn’t great. I’m not sure what the solution could be. I really don’t think the microphones are picking up sound from the headsets. We’ve also just begun replacing older headsets with these high-end plantronics ones, but the problem occurs in both types. Does anyone have any ideas? Thanks.