diff --git a/packages/ludic.audio/README.md b/packages/ludic.audio/README.md
index 2f7d7197..771b742b 100644
--- a/packages/ludic.audio/README.md
+++ b/packages/ludic.audio/README.md
@@ -2,8 +2,8 @@
 
 A game's sounds, and the one door to the runtime's `Audio.*`. Uses nothing.
 
-**`Audio.play` is the interface; the world goes through `aud_emit`.** A click, a chime, a shutter
-and a warning happen in the player's head and are played flat (`aud_ui`). Everything that happens in
+**`aud_ui` is the interface; the world goes through `aud_emit`.** A click, a chime, a shutter
+and a warning happen in the player's head and are played flat (`aud_ui`, on the interface channel). Everything that happens in
 the world - a foot, an axe, a pot, a splash, a call - carries a gain, a pitch and a pan from where it
 is relative to the listener, even when that is the listener's own position. A game that played half
 its world flat had an axe across the camp as loud as your own and a pot at the fire as loud from the
@@ -36,10 +36,10 @@ port AudioFiles { cache_dir: fn() -> string }            # "" (the default): a p
 
 | | |
 | --- | --- |
-| `aud_emit(h, gain, pitch, pan)` | a world sound, as given: the ONE call to `Audio.play_at`, and the one place a float becomes the runtime's Q16.16 |
+| `aud_emit(h, gain, pitch, pan)` | a world sound, as given, handed to `aud_play`: the one place a float becomes the runtime's Q16.16 |
 | `aud_emit_at(h, x, z, range) -> bool` | a world sound at a place, gain, pitch and pan from the listener; false when out of earshot |
 | `aud_gain_at(x, z, range)`, `aud_pan_at(x, z)`, `aud_pitch_at(gain)` | a shaped roll-off (not an inverse square: that is deafening or inaudible in a valley of trees), the side from the listener's heading (ahead and behind centred), and a semitone lower at the edge of hearing |
-| `aud_ui(h)` | an interface sound, flat: the ONE call to `Audio.play` |
+| `aud_ui(h)` | an interface sound, flat, at the interface channel's volume |
 | `aud_music(h)`, `aud_stop_music()`, `aud_master(v)` | the loop and the master volume |
 | `aud_load(path) -> int`, `aud_unpack(path, name)`, `aud_tried()`, `aud_live()` | a clip, loaded past `Audio.load`'s blind spot; how many were asked for and how many loaded |
 | `aud_wav_seconds(path, fallback)` | a PCM WAV's length from its header, for re-triggering a loop before it ends |
@@ -58,8 +58,8 @@ indistinguishable from a working one.
 ## The guard
 
 A game keeps the rule with a grep (Maroon Lake's `tests/audio.sh`): nothing outside this package
-names `Audio.*`, `Audio.play` appears once here (in `aud_ui`) and `Audio.play_at` once (in
-`aud_emit`), and the game calls `aud_ui` only for its interface sounds.
+names `Audio.*`, `Audio.play_at` appears once here (in `aud_play`, which `aud_emit` and `aud_ui` both
+call) and `Audio.play` not at all, and the game calls `aud_ui` only for its interface sounds.
 
 ## Tests
 
diff --git a/packages/ludic.audio/emit.ludic b/packages/ludic.audio/emit.ludic
index 835c655b..c9e05058 100644
--- a/packages/ludic.audio/emit.ludic
+++ b/packages/ludic.audio/emit.ludic
@@ -1,6 +1,6 @@
-# emit.ludic - the only calls into the runtime's playback. aud_emit is the ONE place a float
-# crosses into Audio.play_at's Q16.16: handed over unconverted, 0.94 as a pitch clamped to 4x and
-# -0.85 as a pan to hard left, and every sound in a valley played fast out of one speaker
+# emit.ludic - the only calls into the runtime's playback: aud_play, under aud_emit and aud_ui, is the ONE
+# place a float crosses into Audio.play_at's Q16.16 - handed over unconverted, 0.94 as a pitch clamped to 4x
+# and -0.85 as a pan to hard left, and every sound in a valley played fast out of one speaker
 export state AudioState {
   last_gain: float = 0.0
   last_pitch: float = 0.0
@@ -17,9 +17,12 @@ export function aud_emit(audio_st: mut AudioState, h: int, gain: float, pitch: f
   audio_st.last_pitch = pitch
   audio_st.last_pan = pan
   audio_st.emitted += 1
-  Audio.play_at(h, fixed(gain), fixed(pitch), fixed(pan))
+  aud_play(h, gain, pitch, pan)
 }
 
+# the ONE call into the runtime's playback, and the one place a float becomes its Q16.16
+function aud_play(h: int, gain: float, pitch: float, pan: float) -> void { Audio.play_at(h, fixed(gain), fixed(pitch), fixed(pan)) }
+
 # a sound at a place in the world, heard within `range` metres: false (and nothing played) when the
 # listener is out of earshot
 export function aud_emit_at(audio_st: mut AudioState, h: int, x: float, z: float, range: float) -> bool {
@@ -33,7 +36,7 @@ export function aud_emit_at(audio_st: mut AudioState, h: int, x: float, z: float
 export function aud_ui(audio_st: mut AudioState, h: int) -> void {
   if h == 0 { return }
   audio_st.emitted += 1
-  Audio.play_at(h, fixed(aud_channel(audio_st, AUD_CH_UI)), fixed(1.0), fixed(0.0))
+  aud_play(h, aud_channel(audio_st, AUD_CH_UI), 1.0, 0.0)
 }
 
 export function aud_music(h: int) -> void { if h != 0 { Audio.play_music(h) } }
diff --git a/packages/ludic.audio/index.ludic b/packages/ludic.audio/index.ludic
index 80e45347..207f6204 100644
--- a/packages/ludic.audio/index.ludic
+++ b/packages/ludic.audio/index.ludic
@@ -1,5 +1,5 @@
-# ludic.audio - Audio.play is the INTERFACE; everything that happens in the world goes through
-# aud_emit with a gain and a pan from where it is. Nothing outside this module names Audio.*.
+# ludic.audio - aud_ui is the INTERFACE (flat, on its channel); everything that happens in the world goes
+# through aud_emit with a gain and a pan from where it is. Nothing outside this module names Audio.*.
 module ludic_audio uses
 numbers float
 import "ports.ludic"