Justin Sherrill wrote: > We occasionally get a sort of feedback/echo noise on our phones > here. (Polycom IP550 / Asterisk 1.8). It lasts for about a second, > and it's described by users as 'jingle bells'.
That's very appropriate for the season. I just hope they're not Todash Chimes. ; ) > It happens when people are using the speakerphone, especially when > it's on both ends. It happens on internal calls, so it's not > something from the PSTN. > > My theory is that the very sensitive speakerphone microphones in > those models are picking up small noises, and then picking up their > own playback of the noise, which leads to the feedback sound. It > repeats, which is why it sounds like an echo. Your theory sounds correct to me. You've described acoustic echo and that is the most prevalent type for internal VoIP calls. > I think turning rxgain/txgain down may make a difference, but I > haven't tried it yet. Has anyone else experienced something > similar? I believe rxgain and txgain only apply to DAHDI channels. The first thing I would try is reducing the speakerphone volume settings on the Polycom IP550s. Regards, Matthew Roth InterMedia Marketing Solutions Software Engineer and Systems Developer -- _____________________________________________________________________ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- New to Asterisk? Join us for a live introductory webinar every Thurs: http://www.asterisk.org/hello asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
