Add notes on ALSA

1 files changed, 28 insertions, 1 deletions

diff --git a/playbook.org b/playbook.org
index 4f99f066..80e3bbf9 100644
--- a/playbook.org
+++ b/playbook.org
@@ -479,4 +479,31 @@ Exceptions:
 - Try to record name pronunciation
 - Encourage webcam for Q&A, although make it clear that it's totally optional
 - Possible picture-in-picture approach to maximize screen real estate
-  
+** Experiment with setup to allow MPV / BBB sound isolation
+
+Set MIC and OUTPUT appropriately.
+
+#+begin_src sh :eval no
+MIC=alsa_input.usb-046d_0819_A68D6BE0-02.mono-fallback
+OUTPUT=alsa_output.pci-0000_00_1b.0.analog-stereo
+if [ "$1" == "-u" ]; then
+  pactl unload-module module-loopback
+  pactl unload-module module-null-sink
+else
+  pacmd load-module module-null-sink sink_name=recording sink_properties=device.description=recording channels=2
+  pacmd load-module module-null-sink sink_name=mpv sink_properties=device.description=mpv
+  pacmd load-module module-loopback source=$MIC sink=recording
+  pacmd load-module module-loopback source=mpv.monitor sink=recording
+  pacmd load-module module-loopback source=recording.monitor sink=$OUTPUT
+fi
+#+end_src
+
+You can probably then use =pavucontrol= (choose All Streams instead of
+Applications on the Playback tab) or something like the following to
+redirect the mpv output to the mpv sink.
+
+#+begin_src sh :eval no
+pacmd list-sink-inputs  # notice the
+pacmd move-sink-input 1 mpv
+#+end_src
+