diff --git a/spa/plugins/support/null-audio-sink.c b/spa/plugins/support/null-audio-sink.c
index ad2c4db2a..98ff6562b 100644
--- a/spa/plugins/support/null-audio-sink.c
+++ b/spa/plugins/support/null-audio-sink.c
@@ -37,7 +37,6 @@ struct props {
 	uint32_t format;
 	uint32_t channels;
 	uint32_t rate;
-	uint32_t n_pos;
 	uint32_t pos[SPA_AUDIO_MAX_CHANNELS];
 	char clock_name[64];
 	unsigned int debug:1;
@@ -49,7 +48,6 @@ static void reset_props(struct props *props)
 	props->format = 0;
 	props->channels = 0;
 	props->rate = 0;
-	props->n_pos = 0;
 	strncpy(props->clock_name, DEFAULT_CLOCK_NAME, sizeof(props->clock_name));
 	props->debug = false;
 	props->driver = true;
@@ -469,10 +467,10 @@ port_enum_formats(struct impl *this,
 				SPA_FORMAT_AUDIO_channels, SPA_POD_CHOICE_RANGE_Int(DEFAULT_CHANNELS, 1, INT32_MAX),
 				0);
 		}
-		if (this->props.n_pos != 0) {
+		if (this->props.channels != 0) {
 			spa_pod_builder_prop(builder, SPA_FORMAT_AUDIO_position, 0);
 			spa_pod_builder_array(builder, sizeof(uint32_t), SPA_TYPE_Id,
-					this->props.n_pos, this->props.pos);
+					this->props.channels, this->props.pos);
 		}
 		*param = spa_pod_builder_pop(builder, &f[0]);
 		break;
@@ -888,10 +886,10 @@ static inline void parse_position(struct impl *this, const char *val, size_t len
         if (spa_json_enter_array(&it[0], &it[1]) <= 0)
                 spa_json_init(&it[1], val, len);
 
-	this->props.n_pos = 0;
+	this->props.channels = 0;
 	while (spa_json_get_string(&it[1], v, sizeof(v)) > 0 &&
-	    this->props.n_pos < SPA_AUDIO_MAX_CHANNELS) {
-		this->props.pos[this->props.n_pos++] = channel_from_name(v);
+	    this->props.channels < SPA_AUDIO_MAX_CHANNELS) {
+		this->props.pos[this->props.channels++] = channel_from_name(v);
 	}
 }
 
@@ -991,9 +989,6 @@ impl_init(const struct spa_handle_factory *factory,
 					"%s", s);
 		}
 	}
-	if (this->props.n_pos > 0)
-		this->props.channels = this->props.n_pos;
-
 	spa_log_info(this->log, NAME " %p: initialized", this);
 
 	return 0;