re-adds radio sounds, properly this time (#8237)

they should have proper pauses and checks and shit, and should actually be properly balanced because I ported these from Bay

code/game/objects/items/devices/radio/radio.dm

@@ -52,6 +52,7 @@ var/global/list/default_medbay_channels = list(
 
 
 	var/obj/item/cell/cell = /obj/item/cell/device
+	var/last_radio_sound = -INFINITY
 
 /obj/item/device/radio
 	var/datum/radio_frequency/radio_connection
@@ -312,6 +313,9 @@ var/global/list/default_medbay_channels = list(
 	if(!radio_connection)
 		set_frequency(frequency)
 
+	if(loc == M)
+		playsound(loc, 'sound/effects/walkietalkie.ogg', 5, 0, -1, required_asfx_toggles = ASFX_RADIO)
+
 	/* Quick introduction:
 		This new radio system uses a very robust FTL signaling technology unoriginally
 		dubbed "subspace" which is somewhat similar to 'blue-space' but can't