diff --git a/spa/plugins/audioconvert/channelmix.c b/spa/plugins/audioconvert/channelmix.c
index f4e62be57..90f845a64 100644
--- a/spa/plugins/audioconvert/channelmix.c
+++ b/spa/plugins/audioconvert/channelmix.c
@@ -145,6 +145,7 @@ struct impl {
 	struct spa_cpu *cpu;
 	uint32_t quantum_limit;
 
+	enum spa_direction direction;
 	struct spa_io_position *io_position;
 
 	struct spa_hook_list hooks;
@@ -360,7 +361,7 @@ static int setup_convert(struct impl *this,
 	if ((res = channelmix_init(&this->mix)) < 0)
 		return res;
 
-	remap_volumes(this, src_info);
+	remap_volumes(this, this->direction == SPA_DIRECTION_INPUT ? src_info : dst_info);
 	set_volume(this);
 
 	emit_props_changed(this);
@@ -714,7 +715,7 @@ static int apply_props(struct impl *this, const struct spa_pod *param)
 		}
 	}
 	if (changed) {
-		struct port *port = GET_IN_PORT(this, 0);
+		struct port *port = GET_PORT(this, this->direction, 0);
 		if (have_soft_volume)
 			p->have_soft_volume = true;
 		else if (have_channel_volume)
@@ -1579,6 +1580,12 @@ impl_init(const struct spa_handle_factory *factory,
 			this->props.n_channels = parse_position(this->props.channel_map, s, strlen(s));
 		else if (spa_streq(k, "clock.quantum-limit"))
 			spa_atou32(s, &this->quantum_limit, 0);
+		else if (spa_streq(k, "factory.mode")) {
+			if (spa_streq(s, "merge"))
+				this->direction = SPA_DIRECTION_OUTPUT;
+			else
+				this->direction = SPA_DIRECTION_INPUT;
+		}
 		else
 			channelmix_set_param(this, k, s);
 
diff --git a/spa/plugins/audioconvert/merger.c b/spa/plugins/audioconvert/merger.c
index 7ff696048..3a1de2040 100644
--- a/spa/plugins/audioconvert/merger.c
+++ b/spa/plugins/audioconvert/merger.c
@@ -386,10 +386,13 @@ static int impl_node_enum_params(void *object, int seq,
 
 	case SPA_PARAM_Props:
 	{
+#if 0
 		struct props *p = &this->props;
 		struct spa_pod_frame f[2];
+#endif
 
 		switch (result.index) {
+#if 0
 		case 0:
 			spa_pod_builder_push_object(&b, &f[0],
                                 SPA_TYPE_OBJECT_Props, id);
@@ -422,6 +425,7 @@ static int impl_node_enum_params(void *object, int seq,
 			spa_pod_builder_pop(&b, &f[1]);
 			param = spa_pod_builder_pop(&b, &f[0]);
 			break;
+#endif
 		default:
 			return 0;
 		}