Hi ProfTech, the echo involved both PSTN and VOIP, seemingly randomly but mostly on incoming calls. I have been in contact with the Obihai helpdesk, who very kindly helped me troubleshoot the issues.
They changed the setting in your OBi202 of both PHONE port1 and PHONE port2, they said they reduced the value of the TXgain and RXgain settings.
That in itself didn't seem to do anything to eliminate the problem, but then they said they had made "further modifications" (which they didn't specify) and two days later it seems like that solved it... we haven't had echos since on the 5 or 6 calls we made. So far so good
QBZappy, I'd be interested to know too if that is a fluke or a feature
I get the male robot voice who informs me IV network status not available, so I'm assuming that's the way the 202 works! I'd say that is a big thing to consider for people with a flaky Internet connection who rely on their landline a lot!
PS THANK you, ianobi for referring me how to send a ticket, the staff have been very helpful