Audacity - make back mic default
 

I just setup Audacity on a CentOS machine and after battling with getting sound to work right (why is sound so confusing in Linux, there's like a million devices/inputs etc to pick from) I got it to semi work, but for recording, I also get an option for front and back mic. Every time I reboot, it defaults to front. There is no front. Only back. How do I set default to back? I don't see any options like that in the actual settings, that option is only on the main window on the top right. There's no option there either to set it default.

It depends on your setup. With pulseaudio you can use pavucontrol to configure most of that stuff. Using alsa natively and you have the .asoundrc file to customize (dsnoop for inputs). There probably is a front mic as the headphone out often has a mic input for headset configurations. With jackd it's on the CLI that starts jackd. ... -d alsa -d hw:0,1 ...

When I do recording I tend towards a pulseaudio setup since various applications speak that lingo better. And without it, you're often left with ONLY channel 1 (left) as the input. Or selecting to record ALL available channels to extract the one that you're actually plugged into if it's not the first channel. Ardour is often better for recording. But audacity is easier to edit audio with IMO.

Whatever is default is what my "setup" is. CentOS 6.8 is the OS. I saw something called Alsa somewhere but it was the only option, I can't recall, and it might be a pain to troubleshoot given that PC has no internet so no way to easily google/try stuff. Saw Pulseaudio and a bunch of other options elsewhere. Overall audio in Linux is rather convoluted. Keep clicking stuff until it works basically. Out of the 30+ input/output choices there was I had no idea so it was pretty much a guessing game till it worked. I mostly got it working, just need a way to force the back mic to be default. There is not even a front mic.

$ pgrep pulseaudio

If that returns a number (pid), then you're using pulseaudio.

$ pavucontrol

To adjust settings / defaults if you are using pulseaudio.

There are many more options beyond pulseaudio for audio, but pulseaudio tends to be the default. You can examine your system through various other means.

$ lsmod | grep -i snd

Most ALSA driver modules begin with snd- which shows up as snd_ in the lsmod output. You can also examine the various files in /proc/asound/ to see what drivers and names are associated with things. Information that is mostly useful if you're NOT using pulseaudio.

$ cat /proc/asound/cards

The index number in front of the cards listed is important, the default soundcard has an index of 0. If you have a soundcard and it doesn't show up there you either disabled it in the bios or there's other driver / hardware issues.

What is pulseaudio and alsa and all that anyway? Drivers? If I go under multimedia it also lists a whole bunch of sound cards, when I only have one. I have "default" set to top for both record and play. Though it gives no options to configure anything more from there. There was two sound cards in this system so think that caused lot of weird things to happen, I was constantly getting startup prompts about a sound card that has been removed asking me if I want the system to forget it. I said no each time in case I would cause it to forget something important. I did end up removing the add on sound card so I can use just the built on, to avoid confusion. It was a Sound Blaster Audigy. Not sure what the built on is. The mobo is a Gigabyte if I recall.

I might end up reinstalling though, it's a server OS (CentOS 6.8) and the GUI is complete garbage, it's super glichy and stuff, so I might just install an OS that is more desktop oriented and hopefully at same time everything else will just work better such as better audio defaults. Audacity randomly keeps popping weird messages about latency or other stuff like that which I have to keep hitting cancel or ok. Older folk may use this so I need no messages of that kind to be popping up because that will usually put those people to a dead stop as they won't know what to do. Well I don't know what to do either other then clicking cancel or ok. :P

There are very few modern systems that don't have multiple soundcards. Typically your motherboard has a soundcard, your video card has a soundcard (output only), and your webcam has a soundcard (input only). Even in the olden days your dialup modem was a soundcard of sorts.

ALSA is a set of drivers embedded into the linux kernel. It used to be it's own project along side another (commercial) soundcard driver option called OSS. Where jackd is a low latency interface that you can stack (optionally) on top of the alsa driver. Once you chose your method and set a default, the only changes to audacity should be to set your preferences to use "system defaults". You might also have to set the number of channels to record to a higher number so you get the track on the connection you intend to record from. Audacity tends to capture available sources from channel 1 first, if you want channel 3, you need to capture 1, 2, and 3 (and then delete 1 and 2). Ardour is a little better at selecting a source, but kind of requires the jackd layer. And pulseaudio is a little better at fudging the line between intention and physical hardware.

There are other distros better at sound things. The avlinux option is well liked. And others like ubuntustudio. But everything has it's set of quirks and annoyances. Even though they are all derived from basically the same set of sources.