I officially began playing with Svxlink today…my testing setup consists of a Raspberry Pi running Arch, a CM118 USB sound card, a Diesel brand comms speaker, a 1/8" M to 1/8" M cable plugged into the input of the audio card and the output of a Icom F21.

I configured everything to run under CW ID. I configured alsamixer as best I could (I have the volume correct for the current configuration) but currently I get errors from the Icom's volume being too loud (apparently it is clipping in VOX setting). Now I just get to figure out where to go from there.

They've added quite a few features since I last looked into the project. One of the big ones that caught my attention are the ability to use GPIO pins as well as ip linking. I think I'm just gonna play around with this for a bit longer. May even adapt a few repeaters to use the system (I've got a couple of R100's that would be a good start option).

I've been a ham since the late 70's and feel like a newbie when you guys post stuff like this!  I think there's about a half dozen words I've never even heard before.  I even have some of the hardware you mentioned, except it's the latest pcDuino instead of a Pi, and I did get an RTL SDR dongle to work on it with SDR#.  Since then it's been tossed in a box and I've been working on radios with glowing tubes for fun.  

Keep up the good work, I'll be quietly watching from the sidelines and maybe I'll jump back into this new tech someday.

Have you tried using pulseaudio? It has wrappers for alsa and lets you configure both application and device levels easily in pavucontrol

I'll look at it.

The input is looking for something more in the form of line-levels. Just the nature of the sound card. It's setup for picking up a un-amplified microphone, not a 5W speaker output. Some of the guys over at Svxlink suggested a voltage divider on the output.