> I changed from a tdm100B card over to an Adtran 750 as I added more PSTN > lines last week. I have a Sangoma A104u card and 12 channels FXO > connected to PSTN lines. I am experiencing very poor audio quality with > hum on the lines and poor volume. When I connected the Adtrans I > upgraded the firmware to the latest and reset the config to the factory > default. I also upgraded Asterisk to 1.2. > I am at a loss to explain why the quality has become so poor, has anyone > any advice?
I'm not useing a 750, but just suggesting a possibility... Check to ensure the fxo lines have proper termination/impenance settings. 600 ohm in the US, etc. There was someone trying to use another channel bank some time ago in the Colorado area (I forgot the exact make/model), and the fxo card specs were actually listed as 15,000 ohms (no 600/900 ohm at all). He had the same 'hum' issue, and that was certainly understandable. _______________________________________________ --Bandwidth and Colocation sponsored by Easynews.com -- Asterisk-Users mailing list [email protected] http://lists.digium.com/mailman/listinfo/asterisk-users To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
