diff --git a/spa/include/spa/utils/defs.h b/spa/include/spa/utils/defs.h
index 58d6a9151..4654d4a10 100644
--- a/spa/include/spa/utils/defs.h
+++ b/spa/include/spa/utils/defs.h
@@ -107,6 +107,12 @@ struct spa_param_info {
 	SPA_MIN(SPA_MAX(_v, _low), _high);		\
 })
 
+#define SPA_SWAP(a,b)					\
+({							\
+	__typeof__(a) _t = (a);				\
+	a = b; b = _t;					\
+})
+
 #define SPA_TYPECHECK(type,x)		\
 ({	type _dummy;			\
 	typeof(x) _dummy2;		\
diff --git a/src/modules/module-client-node/client-node.c b/src/modules/module-client-node/client-node.c
index 3b2973802..b00eb7f6a 100644
--- a/src/modules/module-client-node/client-node.c
+++ b/src/modules/module-client-node/client-node.c
@@ -792,10 +792,10 @@ impl_node_port_set_io(struct spa_node *node,
 		      uint32_t id,
 		      void *data, size_t size)
 {
-	/* ignore io on the node itself, weonly care about the io on the
+	/* ignore io on the node itself, we only care about the io on the
 	 * port mixers, the io on the node ports itself is handled on the
 	 * client side */
-	return 0;
+	return -EINVAL;
 }
 
 static int
diff --git a/src/modules/module-client-node/client-stream.c b/src/modules/module-client-node/client-stream.c
index 7a02fa7e4..87062ad95 100644
--- a/src/modules/module-client-node/client-stream.c
+++ b/src/modules/module-client-node/client-stream.c
@@ -106,6 +106,9 @@ struct impl {
 	struct spa_buffer **buffers;
 	uint32_t n_buffers;
 	struct pw_memblock *mem;
+
+	struct pw_control_link control;
+	struct pw_control_link notify;
 };
 
 /** \endcond */
@@ -187,18 +190,19 @@ static void try_link_controls(struct impl *impl)
 
 	port = impl->client_port;
 
-
 	pw_log_debug(NAME " %p: trying controls", impl);
 	spa_list_for_each(cout, &port->control_list[SPA_DIRECTION_OUTPUT], port_link) {
 		spa_list_for_each(cin, &target->control_list[SPA_DIRECTION_INPUT], port_link) {
-			if ((res = pw_control_link(cout, cin)) < 0)
+			if ((res = pw_control_add_link(cout, 0, cin, 0, &impl->control)) < 0)
 				pw_log_error("failed to link controls: %s", spa_strerror(res));
+			break;
 		}
 	}
 	spa_list_for_each(cin, &port->control_list[SPA_DIRECTION_INPUT], port_link) {
 		spa_list_for_each(cout, &target->control_list[SPA_DIRECTION_OUTPUT], port_link) {
-			if ((res = pw_control_link(cout, cin)) < 0)
+			if ((res = pw_control_add_link(cout, 0, cin, 0, &impl->notify)) < 0)
 				pw_log_error("failed to link controls: %s", spa_strerror(res));
+			break;
 		}
 	}
 }
@@ -868,7 +872,8 @@ static int impl_node_process(struct spa_node *node)
 
 	if (impl->direction == SPA_DIRECTION_OUTPUT) {
 		if (!(status & SPA_STATUS_HAVE_BUFFER))
-			spa_log_warn(this->log, "%p: process underrun", this);
+			spa_log_warn(this->log, "%p: '%s' id:%d underrun",
+					this, impl->this.node->info.name, impl->this.node->info.id);
 		trigger = status & SPA_STATUS_NEED_BUFFER;
 	}
 	else
diff --git a/src/pipewire/control.c b/src/pipewire/control.c
index c9933079c..688a7a4f8 100644
--- a/src/pipewire/control.c
+++ b/src/pipewire/control.c
@@ -70,7 +70,7 @@ pw_control_new(struct pw_core *core,
 	this->port = port;
 	this->direction = direction;
 
-	spa_list_init(&this->inputs);
+	spa_list_init(&this->links);
 
         if (user_data_size > 0)
 		this->user_data = SPA_MEMBER(impl, sizeof(struct impl), void);
@@ -92,19 +92,19 @@ pw_control_new(struct pw_core *core,
 void pw_control_destroy(struct pw_control *control)
 {
 	struct impl *impl = SPA_CONTAINER_OF(control, struct impl, this);
-	struct pw_control *other, *tmp;
+	struct pw_control_link *link, *tmp;
 
 	pw_log_debug("control %p: destroy", control);
 
 	pw_control_emit_destroy(control);
 
 	if (control->direction == SPA_DIRECTION_OUTPUT) {
-		spa_list_for_each_safe(other, tmp, &control->inputs, inputs_link)
-			pw_control_unlink(control, other);
+		spa_list_for_each_safe(link, tmp, &control->links, out_link)
+			pw_control_remove_link(link);
 	}
 	else {
-		if (control->output)
-			pw_control_unlink(control->output, control);
+		spa_list_for_each_safe(link, tmp, &control->links, in_link)
+			pw_control_remove_link(link);
 	}
 
 	spa_list_remove(&control->link);
@@ -139,26 +139,45 @@ void pw_control_add_listener(struct pw_control *control,
 	spa_hook_list_append(&control->listener_list, listener, events, data);
 }
 
+static int port_set_io(struct pw_port *port, uint32_t mix, uint32_t id, void *data, uint32_t size)
+{
+	struct spa_node *n;
+	uint32_t p;
+	int res;
+
+	if (port->mix && port->mix->port_set_io) {
+		n = port->mix;
+		p = mix;
+	} else {
+		n = port->node->node;
+		p = port->port_id;
+	}
+	if ((res = spa_node_port_set_io(n,
+			port->direction, p,
+			id, data, size)) < 0) {
+		pw_log_warn("port %p: set io failed %d %s", port,
+				res, spa_strerror(res));
+	}
+	return res;
+}
+
 SPA_EXPORT
-int pw_control_link(struct pw_control *control, struct pw_control *other)
+int pw_control_add_link(struct pw_control *control, uint32_t cmix,
+		struct pw_control *other, uint32_t omix,
+		struct pw_control_link *link)
 {
 	int res = 0;
 	struct impl *impl;
 	uint32_t size;
 
 	if (control->direction == SPA_DIRECTION_INPUT) {
-		struct pw_control *tmp = control;
-		control = other;
-		other = tmp;
+		SPA_SWAP(control, other);
+		SPA_SWAP(cmix, omix);
 	}
 	if (control->direction != SPA_DIRECTION_OUTPUT ||
 	    other->direction != SPA_DIRECTION_INPUT)
 		return -EINVAL;
 
-	/* input control already has a linked output control */
-	if (other->output != NULL)
-		return -EEXIST;
-
 	impl = SPA_CONTAINER_OF(control, struct impl, this);
 
 	pw_log_debug("control %p: link to %p %s", control, other,
@@ -173,43 +192,36 @@ int pw_control_link(struct pw_control *control, struct pw_control *other)
 					     size,
 					     &impl->mem)) < 0)
 			goto exit;
+	}
 
+	if (spa_list_is_empty(&control->links)) {
+		if (control->port) {
+			if ((res = port_set_io(control->port, cmix,
+						control->id,
+						impl->mem->ptr, size)) < 0) {
+				pw_log_warn("control %p: set io failed %d %s", control,
+					res, spa_strerror(res));
+				goto exit;
+			}
+		}
 	}
 
 	if (other->port) {
-		struct pw_port *port = other->port;
-		if ((res = spa_node_port_set_io(port->node->node,
-				     port->direction, port->port_id,
-				     other->id,
-				     impl->mem->ptr, size)) < 0) {
+		if ((res = port_set_io(other->port, omix,
+				other->id, impl->mem->ptr, size)) < 0) {
 			pw_log_warn("control %p: set io failed %d %s", control,
 					res, spa_strerror(res));
 			goto exit;
 		}
 	}
 
-	if (spa_list_is_empty(&control->inputs)) {
-		if (control->port) {
-			struct pw_port *port = control->port;
-			if ((res = spa_node_port_set_io(port->node->node,
-					     port->direction, port->port_id,
-					     control->id,
-					     impl->mem->ptr, size)) < 0) {
-				pw_log_warn("control %p: set io failed %d %s", control,
-					res, spa_strerror(res));
-				/* undo */
-				port = other->port;
-				spa_node_port_set_io(port->node->node,
-	                                     port->direction, port->port_id,
-	                                     other->id,
-	                                     NULL, 0);
-				goto exit;
-			}
-		}
-	}
-
-	other->output = control;
-	spa_list_append(&control->inputs, &other->inputs_link);
+	link->output = control;
+	link->input = other;
+	link->out_port = cmix;
+	link->in_port = omix;
+	link->valid = true;
+	spa_list_append(&control->links, &link->out_link);
+	spa_list_append(&other->links, &link->in_link);
 
 	pw_control_emit_linked(control, other);
 	pw_control_emit_linked(other, control);
@@ -219,47 +231,34 @@ int pw_control_link(struct pw_control *control, struct pw_control *other)
 }
 
 SPA_EXPORT
-int pw_control_unlink(struct pw_control *control, struct pw_control *other)
+int pw_control_remove_link(struct pw_control_link *link)
 {
 	int res = 0;
+	struct pw_control *output = link->output;
+	struct pw_control *input = link->input;
 
-	pw_log_debug("control %p: unlink from %p", control, other);
+	pw_log_debug("control %p: unlink from %p", output, input);
 
-	if (control->direction == SPA_DIRECTION_INPUT) {
-		struct pw_control *tmp = control;
-		control = other;
-		other = tmp;
-	}
-	if (control->direction != SPA_DIRECTION_OUTPUT ||
-	    other->direction != SPA_DIRECTION_INPUT)
-		return -EINVAL;
+	spa_list_remove(&link->in_link);
+	spa_list_remove(&link->out_link);
+	link->valid = false;
 
-	if (other->output != control)
-		return -EINVAL;
-
-	other->output = NULL;
-	spa_list_remove(&other->inputs_link);
-
-	if (spa_list_is_empty(&control->inputs)) {
-		struct pw_port *port = control->port;
-		if ((res = spa_node_port_set_io(port->node->node,
-				     port->direction, port->port_id,
-				     control->id, NULL, 0)) < 0) {
-			pw_log_warn("control %p: can't unset port control io", control);
+	if (spa_list_is_empty(&output->links)) {
+		if ((res = port_set_io(output->port, link->out_port,
+					output->id, NULL, 0)) < 0) {
+			pw_log_warn("control %p: can't unset port control io", output);
 		}
 	}
 
-	if (other->port) {
-		struct pw_port *port = other->port;
-		if ((res = spa_node_port_set_io(port->node->node,
-				     port->direction, port->port_id,
-				     other->id, NULL, 0)) < 0) {
-			pw_log_warn("control %p: can't unset port control io", control);
+	if (input->port) {
+		if ((res = port_set_io(input->port, link->in_port,
+				     input->id, NULL, 0)) < 0) {
+			pw_log_warn("control %p: can't unset port control io", output);
 		}
 	}
 
-	pw_control_emit_unlinked(control, other);
-	pw_control_emit_unlinked(other, control);
+	pw_control_emit_unlinked(output, input);
+	pw_control_emit_unlinked(input, output);
 
 	return res;
 }
diff --git a/src/pipewire/control.h b/src/pipewire/control.h
index aae79d930..26e5be98e 100644
--- a/src/pipewire/control.h
+++ b/src/pipewire/control.h
@@ -74,9 +74,6 @@ void pw_control_add_listener(struct pw_control *control,
 			     const struct pw_control_events *events,
 			     void *data);
 
-int pw_control_link(struct pw_control *control, struct pw_control *other);
-int pw_control_unlink(struct pw_control *control, struct pw_control *other);
-
 #ifdef __cplusplus
 }
 #endif
diff --git a/src/pipewire/link.c b/src/pipewire/link.c
index fbae8ecad..8729b68d0 100644
--- a/src/pipewire/link.c
+++ b/src/pipewire/link.c
@@ -1143,43 +1143,46 @@ static bool pw_node_can_reach(struct pw_node *output, struct pw_node *input)
 	return false;
 }
 
-static void try_link_controls(struct impl *impl, struct pw_port *port, struct pw_port *target)
+static void try_link_controls(struct impl *impl, struct pw_port *output, struct pw_port *input)
 {
 	struct pw_control *cin, *cout;
+	struct pw_link *this = &impl->this;
+	uint32_t omix, imix;
 	int res;
 
+	imix = this->rt.in_mix.port.port_id;
+	omix = this->rt.out_mix.port.port_id;
+
 	pw_log_debug("link %p: trying controls", impl);
-	spa_list_for_each(cout, &port->control_list[SPA_DIRECTION_OUTPUT], port_link) {
-		spa_list_for_each(cin, &target->control_list[SPA_DIRECTION_INPUT], port_link) {
-			if ((res = pw_control_link(cout, cin)) < 0)
+	spa_list_for_each(cout, &output->control_list[SPA_DIRECTION_OUTPUT], port_link) {
+		spa_list_for_each(cin, &input->control_list[SPA_DIRECTION_INPUT], port_link) {
+			if ((res = pw_control_add_link(cout, omix, cin, imix, &this->control)) < 0)
 				pw_log_error("failed to link controls: %s", spa_strerror(res));
+			break;
 		}
 	}
-	spa_list_for_each(cin, &port->control_list[SPA_DIRECTION_INPUT], port_link) {
-		spa_list_for_each(cout, &target->control_list[SPA_DIRECTION_OUTPUT], port_link) {
-			if ((res = pw_control_link(cout, cin)) < 0)
+	spa_list_for_each(cin, &output->control_list[SPA_DIRECTION_INPUT], port_link) {
+		spa_list_for_each(cout, &input->control_list[SPA_DIRECTION_OUTPUT], port_link) {
+			if ((res = pw_control_add_link(cout, imix, cin, omix, &this->notify)) < 0)
 				pw_log_error("failed to link controls: %s", spa_strerror(res));
+			break;
 		}
 	}
 }
 
-static void try_unlink_controls(struct impl *impl, struct pw_port *port, struct pw_port *target)
+static void try_unlink_controls(struct impl *impl, struct pw_port *output, struct pw_port *input)
 {
-	struct pw_control *cin, *cout;
+	struct pw_link *this = &impl->this;
 	int res;
 
 	pw_log_debug("link %p: unlinking controls", impl);
-	spa_list_for_each(cout, &port->control_list[SPA_DIRECTION_OUTPUT], port_link) {
-		spa_list_for_each(cin, &target->control_list[SPA_DIRECTION_INPUT], port_link) {
-			if ((res = pw_control_unlink(cout, cin)) < 0)
-				pw_log_error("failed to unlink controls: %s", spa_strerror(res));
-		}
+	if (this->control.valid) {
+		if ((res = pw_control_remove_link(&this->control)) < 0)
+			pw_log_error("failed to unlink controls: %s", spa_strerror(res));
 	}
-	spa_list_for_each(cin, &port->control_list[SPA_DIRECTION_INPUT], port_link) {
-		spa_list_for_each(cout, &target->control_list[SPA_DIRECTION_OUTPUT], port_link) {
-			if ((res = pw_control_unlink(cout, cin)) < 0)
-				pw_log_error("failed to unlink controls: %s", spa_strerror(res));
-		}
+	if (this->notify.valid) {
+		if ((res = pw_control_remove_link(&this->notify)) < 0)
+			pw_log_error("failed to unlink controls: %s", spa_strerror(res));
 	}
 }
 
@@ -1387,7 +1390,7 @@ void pw_link_destroy(struct pw_link *link)
 
 	pw_node_emit_peer_removed(link->output->node, link->input->node);
 
-	try_unlink_controls(impl, link->input, link->output);
+	try_unlink_controls(impl, link->output, link->input);
 
 	input_remove(link, link->input);
 	output_remove(link, link->output);
diff --git a/src/pipewire/private.h b/src/pipewire/private.h
index 162ca4b02..304ae476c 100644
--- a/src/pipewire/private.h
+++ b/src/pipewire/private.h
@@ -510,6 +510,16 @@ struct pw_port {
         void *user_data;                /**< extra user data */
 };
 
+struct pw_control_link {
+	struct spa_list out_link;
+	struct spa_list in_link;
+	struct pw_control *output;
+	struct pw_control *input;
+	uint32_t out_port;
+	uint32_t in_port;
+	int valid:1;
+};
+
 #define pw_link_emit(o,m,v,...) spa_hook_list_call(&o->listener_list, struct pw_link_events, m, v, ##__VA_ARGS__)
 #define pw_link_emit_destroy(l)			pw_link_emit(l, destroy, 0)
 #define pw_link_emit_free(l)			pw_link_emit(l, free, 0)
@@ -535,6 +545,9 @@ struct pw_link {
 
 	struct spa_hook_list listener_list;
 
+	struct pw_control_link control;
+	struct pw_control_link notify;
+
 	struct {
 		struct pw_port_mix out_mix;	/**< port added to the output mixer */
 		struct pw_port_mix in_mix;	/**< port added to the input mixer */
@@ -690,11 +703,7 @@ struct pw_control {
 	struct spa_list port_link;	/**< link in port control_list */
 
 	enum spa_direction direction;	/**< the direction */
-
-	struct pw_control *output;	/**< pointer to linked output control */
-
-	struct spa_list inputs;		/**< list of linked input controls */
-	struct spa_list inputs_link;	/**< link in linked input control */
+	struct spa_list links;		/**< list of pw_control_link */
 
 	uint32_t id;
 	int32_t size;
@@ -704,7 +713,6 @@ struct pw_control {
 	void *user_data;
 };
 
-
 /** Find a good format between 2 ports */
 int pw_core_find_format(struct pw_core *core,
 			struct pw_port *output,
@@ -835,6 +843,12 @@ pw_control_new(struct pw_core *core,
 	       uint32_t id, uint32_t size,
 	       size_t user_data_size		/**< extra user data */);
 
+int pw_control_add_link(struct pw_control *control, uint32_t cmix,
+		struct pw_control *other, uint32_t omix,
+		struct pw_control_link *link);
+
+int pw_control_remove_link(struct pw_control_link *link);
+
 void pw_control_destroy(struct pw_control *control);
 
 /** \endcond */
diff --git a/src/tools/pipewire-monitor.c b/src/tools/pipewire-monitor.c
index f39a88293..0dc410b72 100644
--- a/src/tools/pipewire-monitor.c
+++ b/src/tools/pipewire-monitor.c
@@ -162,6 +162,7 @@ static void print_params(struct proxy_data *data, char mark)
 
 	printf("%c\tparams:\n", mark);
 	spa_list_for_each(p, &data->param_list, link) {
+		printf("%c\t  id:%u\n", mark, p->id);
 		if (spa_pod_is_object_type(p->param, SPA_TYPE_OBJECT_Format))
 			spa_debug_format(10, NULL, p->param);
 		else