I have a problem with my SPA525G2 causing what I believe is acoustic echo on the remote end.
When I use the phone's speakerphone, the party at the other end of the call can hear an echo of their own voice. Typically, the echo seems to vary between about 100ms and 300ms (to my untrained ear). I can reliably reproduce it on every call and several remote parties have complained. I have also managed to record it via the SPA525G2's call record function. Switching to handset fixes the problem.
I have tried reducing the speakerphone's audio input gain from 0db to -6db, then -9db (via additional gain) but the problem persists. I am guessing that the phone's mic is picking up the speakerphone audio and relaying it back to the remote party, ie the mic and speaker are acoustically coupled.
Does anyone have any experience with this issue? Any ideas how I might solve it? If it's acoustic feedback, is it possible to physically decouple the mic and speaker - perhaps a baffle or something similar around the mic??
The phone is set up to resister with a hosted SIP provider, which appears to work well - I can make and receive calls reliably and jitter/latancy for the calls I've monitored all seem ok. It is running fw 7.5.5.