Music on Hold, Streaming from Computers Line-in

Not sure what is what. Looks like I might use some “tips” or “tricks”. Here is the problem…

I have successfully setup the MOH from Line-IN. I can hear the music when on hold, but the music has a distinct glitch in it. The glitch is kind of thump that pulses every 1/2 second, it is pretty smooth and the volume is lower than of the music and in some instances not audible, but kind of breaks-up the music a little. It is very annoying.

I did try few different formats, S16_LE, S8, A_LAW and few others some do not work at all, but the once that work all work the same and I can hear the glitch and it is the same.

I have tried to manipulate the buffer size and had settings from 8 to 4096 and none of that made any change to the glitch or the quality of the audio.

I have tried different types (-t option) WAV and RAW, but both the same, glitch is there in both.

I have also recorded a wave file using the same arecord settings as I use for MOH, and the resulted file is clear and has no glitches. So that lets me know that the glitch is not from hardware.

Anyone can suggest anything, please do. Thank you

Sounds like (no pun intended) the sound card is sharing an interrupt. ‘lspci’ may provide some insight.

All the Asterisk line in solutions have a ton of overhead in my opinion. If you need to do this run shoutcast on another machine.

I just would like to have the one box solution. We have only few extensions so I would think that PC has plenty of overhead left for a line-in script. On top of that I have pretty beefy workstation that runs our FreePBX. I will check how line-in will work with a USB Sound Card, I have one laying around. If you can point me out to how make arecord to use USB card or how to make USB card to be the default device alsa uses, it would be a great help. Thank you,

I don’t have much experience with ALSA. I would disable the motherboard sound. Just make sure the USB device is supported by Red Hat Linux.