This might be caused by where you're injecting your audio into the TX radio. Whats the model/make of the TX radio you're using? ________________________________ From: Eric Guth [mailto:eric@efratnetworks.com] Sent: Tuesday, May 08, 2012 10:13 PM To: Ken Cc: app_rpt-users@ohnosec.org Subject: Re: [App_rpt-users] Noise reduction on receive audio from Allstar I am referring to audio coming from the link and transmitted to me on my node. 73, Eric. 4Z5UG On May 9, 2012, at 3:21 AM, "Ken" <ke2n@cs.com> wrote: Is it possible you are getting discriminator audio from your radio, but telling asterisk that it is "flat" audio? That would make everything high pitched and noisy Ken From: app_rpt-users-bounces@ohnosec.org [mailto:app_rpt-users-bounces@ohnosec.org] On Behalf Of Eric Guth Sent: Tuesday, May 08, 2012 5:34 PM To: app_rpt-users@ohnosec.org Subject: [App_rpt-users] Noise reduction on receive audio from Allstar Folks, I notice that when hams are noisy into their Allstar node or the repeater connected to the Allstar node, the noise on their signal seems to be higher pitch and accentuated. Some folks are always noisy and therefore difficult to copy. Does anyone else have this problem, and has anyone reduced the noise with either software running on the server or some hardware inserted in between the audio from the URI or CM108 dongle to the transmitter? I was thinking a DSP audio filter (more expensive than my whole node). 73, Eric 4Z5UG