We are having a problem with audio quality coming through the Wowza streaming engine. All audio loses frequency above 13khz. We understand that most human beings do not readily hear distinct sounds in that frequency, but many of the artists streaming through our service do indeed notice the issue. We have tried different configuration settings in “transcode.xml”, changing the “PassThru” and changing bitrate, but nothing seems to help - except turning off transcoding altogether, which doesn’t see a reasonable option. Aside from audio bitrate and codec, are there any other configuration options we can try? What might be causing this “low pass filter” effect? It should be possible to get some AAC audio that does not lose the higher end of the spectrum all the time.
All ideas welcome - we’re on the cusp of searching for other solutions…