Fix sound_emitter destruction behaviour and nullref runtimes

code/datums/datumvars.dm

@@ -141,7 +141,7 @@
 		body += "<option value='?_src_=vars;toggle_aliasing=\ref[D]'>Toggle Transform Aliasing</option>"
 	if(istype(D,/obj/item/weapon/gun))
 		body += "<option value='?_src_=vars;projectile_edit=\ref[D]'>Edit Projectile Variables</option>"
-	if(has_initialized_sound_emitter(D))
+	if(istype(D, /atom/movable))
 		body += "<option value='?_src_=vars;halt_sound=\ref[D]'>Stop Sound</option>"
 
 
@@ -997,9 +997,9 @@ function loadPage(list) {
 		if (!check_rights(R_DEBUG))
 			return
 
-		var/atom/A = locate(href_list["halt_sound"])
-		if(!istype(A) || !has_initialized_sound_emitter(A))
-			to_chat(src, "This can only be done to atoms that have an initialized sound emitter")
+		var/atom/movable/A = locate(href_list["halt_sound"])
+		if(!istype(A) || (A.sound_emitter == null))
+			to_chat(src, "This can only be done to atom/movables that have an initialized sound emitter")
 			return
 
 		A.sound_emitter.stop()

code/modules/sound/sound_emitter.dm

@@ -11,9 +11,13 @@
 	  The subscription is driven by the SZM, which maintains a hashmap of sound_emitter locations.
 */
 
-/atom
+/atom/movable
 	var/datum/sound_emitter/sound_emitter
 
+/atom/movable/Destroy()
+	qdel(sound_emitter)
+	return ..()
+
 /atom/proc/setup_sound()
 	return
 
@@ -91,7 +95,7 @@
 /datum/sound_emitter/Destroy()
 	sound_emitter_collection.remove(src)
 	sound_zone_manager.unregister_emitter(src)
-	deactivate();
+	deactivate()
 	if (sounds)
 		sounds.Cut()
 		sounds = null
@@ -219,7 +223,7 @@
 // halt sounds to clients, unregister from dynamic updates
 /datum/sound_emitter/proc/deactivate()
 	active_sound = null
-  
+
 	INVOKE_EVENT(src, /event/sound_stopped, "emitter" = src)
 
 /datum/sound_emitter/proc/update_env_effect()

code/modules/sound/sound_listener_context/sound_listener_context.dm

@@ -54,13 +54,15 @@
 	var/mob/proxy = null
 	var/list/current_channels_by_emitter = list()
 	var/list/free_channels = list()
+	var/list/audible_emitters = list()
 	var/range = null
 
 /datum/sound_listener_context/New(client/C, mob/P, hearing_range = world.view)
 	client = C
 	proxy = P
 	current_channels_by_emitter = list()
 	free_channels = list()
+	audible_emitters = list()
 	for (var/i = CHANNEL_RESERVABLE_MIN, i <= CHANNEL_RESERVABLE_MAX, i++)
 		free_channels += i
 	range = hearing_range
@@ -69,6 +71,9 @@
 /datum/sound_listener_context/Destroy()
 	for (var/datum/sound_emitter/E in current_channels_by_emitter)
 		release(E)
+	for (var/datum/sound_emitter/E in audible_emitters)
+		unsubscribe_from(E)
+	audible_emitters.Cut()
 	free_channels.Cut()
 	current_channels_by_emitter.Cut()
 	sound_zone_manager.unregister_listener(src)
@@ -96,7 +101,7 @@
 	// which channel this client is using for this emitter
 	var/chan = current_channels_by_emitter[E]
 	if (!chan)
-		CRASH("listener_context attempted to release [E] with no channel, possible double-release or other fuckery")
+		return //no channel to release, no sound to stop (hopefully)
 	// flush it
 	var/sound/nullsound = sound(file = null)
 	nullsound.channel = chan
@@ -106,8 +111,6 @@
 	current_channels_by_emitter -= E
 	free_channels += chan
 
-	unsubscribe_from(E)
-
 /datum/sound_listener_context/proc/reset_proxy(mob/P)
 	sound_zone_manager.unregister_listener(src)
 	proxy = P
@@ -131,7 +134,6 @@
 	E.register_event(/event/sound_stopped, src, nameof(src::stop_hearing()))
 	E.register_event(/event/sound_pushed, src, nameof(src::hear_once()))
 
-
 /datum/sound_listener_context/proc/unsubscribe_from(datum/sound_emitter/E)
 	E.unregister_event(/event/sound_updated, src, nameof(src::on_sound_update()))
 	E.unregister_event(/event/sound_started, src, nameof(src::start_hearing()))
@@ -161,13 +163,7 @@
 	client << S
 
 /datum/sound_listener_context/proc/stop_hearing(datum/sound_emitter/emitter)
-	var/chan = current_channels_by_emitter[emitter]
-	if (!chan)
-		return // already can't hear it (probably)
-	var/sound/nullsound = sound(file = null)
-	nullsound.channel = chan
-	nullsound.status = SOUND_UPDATE | SOUND_MUTE
-	client << nullsound
+	release(emitter)
 
 /datum/sound_listener_context/proc/on_sound_update(datum/sound_emitter/emitter)
 	var/chan = current_channels_by_emitter[emitter]
@@ -184,6 +180,9 @@
 /datum/sound_listener_context/proc/on_enter_range(datum/sound_emitter/E)
 	start_hearing(E) // this can throw if channel reservation fails, subscribe after its safe
 	subscribe_to(E)
+	audible_emitters |= E
 
 /datum/sound_listener_context/proc/on_exit_range(datum/sound_emitter/E)
-	release(E)
+	stop_hearing(E)
+	unsubscribe_from(E)
+	audible_emitters -= E

code/modules/sound/sound_zone_manager.dm

@@ -114,7 +114,7 @@ var/global/datum/sound_zone_manager/sound_zone_manager = new
 				CRASH("Found a listener with no client or endpoint client")
 			var/datum/sound_listener_context/context = client.listener_context
 
-			if (E in context.current_channels_by_emitter)
+			if (E in context.audible_emitters)
 				if (!E.contains(listener))
 					context.on_exit_range(E)
 				else
@@ -197,7 +197,7 @@ var/global/datum/sound_zone_manager/sound_zone_manager = new
 	var/datum/sound_listener_context/context = receive_client.listener_context
 
 	var/list/current = list()
-	for (var/datum/sound_emitter/E in context.current_channels_by_emitter)
+	for (var/datum/sound_emitter/E in context.audible_emitters)
 		current[E] = TRUE
 	var/list/fresh = list()