Not every control has a group as the manual wording says, i.e.
$ sndioctl
input.level=0.486
input.mute=0
output.level=1.000
output.mute=0
app/aucat0.level=1.000
Feedack? OK?
Index: sndioctl.1
===================================================================
RCS file: /cvs/src/usr.bin/sndioctl/sndioctl.1,v
retrieving revision 1.14
diff -u -p -r1.14 sndioctl.1
--- sndioctl.1 27 May 2020 17:34:45 -0000 1.14
+++ sndioctl.1 20 Nov 2020 16:46:45 -0000
@@ -72,8 +72,8 @@ The set of available controls depends on
Commands use the following two formats to display and change
controls respectively:
.Pp
-.Dl group/stream[channel].function
-.Dl group/stream[channel].function=value
+.Dl [group/]stream[channel].function
+.Dl [group/]stream[channel].function=value
.Pp
On the left-hand side are specified the control group (if any),
the affected stream name, and the optional channel number.
