diff --git a/src/modules/module-avbtp/acmp.c b/src/modules/module-avbtp/acmp.c
index 06e3fffe7..de2cf3555 100644
--- a/src/modules/module-avbtp/acmp.c
+++ b/src/modules/module-avbtp/acmp.c
@@ -30,40 +30,209 @@
 #include "acmp.h"
 #include "internal.h"
 
+struct pending {
+	struct spa_list link;
+	uint64_t last_time;
+	uint64_t timeout;
+	uint16_t old_sequence_id;
+	uint16_t sequence_id;
+	uint16_t retry;
+	size_t size;
+	void *ptr;
+};
+
 struct acmp {
 	struct server *server;
 	struct spa_hook server_listener;
+
+#define PENDING_TALKER		0
+#define PENDING_LISTENER	1
+#define PENDING_CONTROLLER	2
+	struct spa_list pending[3];
+	uint16_t sequence_id[3];
 };
 
+static void *pending_new(struct acmp *acmp, uint32_t type, uint64_t now, uint32_t timeout_ms,
+		const struct avbtp_packet_acmp *m, size_t size)
+{
+	struct pending *p;
+	struct avbtp_packet_acmp *pm;
+	p = calloc(1, sizeof(*p) + size);
+	if (p == NULL)
+		return NULL;
+	p->last_time = now;
+	p->timeout = timeout_ms * SPA_NSEC_PER_MSEC;
+	p->old_sequence_id = ntohs(m->sequence_id);
+	p->sequence_id = acmp->sequence_id[type]++;
+	p->size = size;
+	p->ptr = SPA_PTROFF(p, sizeof(*p), void);
+	memcpy(p->ptr, m, size);
+	pm = p->ptr;
+	pm->sequence_id = htons(p->sequence_id);
+	spa_list_append(&acmp->pending[type], &p->link);
+
+	return p->ptr;
+}
+
+static struct pending *pending_find(struct acmp *acmp, uint32_t type, uint16_t sequence_id)
+{
+	struct pending *p;
+	spa_list_for_each(p, &acmp->pending[type], link)
+		if (p->sequence_id == sequence_id)
+			return p;
+	return NULL;
+}
+
+static void pending_free(struct acmp *acmp, struct pending *p)
+{
+	spa_list_remove(&p->link);
+	free(p);
+}
+
 struct msg_info {
 	uint16_t type;
 	const char *name;
-	int (*handle) (struct acmp *acmp, const void *p, int len);
+	int (*handle) (struct acmp *acmp, uint64_t now, const void *m, int len);
 };
 
-static int reply_not_supported(struct acmp *acmp, const void *p, int len)
+static int reply_not_supported(struct acmp *acmp, const void *m, int len)
 {
 	struct server *server = acmp->server;
 	uint8_t buf[len];
 	struct avbtp_packet_acmp *reply = (struct avbtp_packet_acmp*)buf;
 
-	memcpy(reply, p, len);
+	memcpy(reply, m, len);
 	AVBTP_PACKET_ACMP_SET_STATUS(reply, AVBTP_ACMP_STATUS_NOT_SUPPORTED);
 
 	return avbtp_server_send_packet(server, reply->hdr.eth.src, reply, len);
 }
 
+static int retry_pending(struct acmp *acmp, uint64_t now, struct pending *p)
+{
+	struct server *server = acmp->server;
+	struct avbtp_packet_acmp *cmd = p->ptr;
+	p->retry++;
+	p->last_time = now;
+	return avbtp_server_send_packet(server, cmd->hdr.eth.dest, cmd, p->size);
+}
+
+static int handle_connect_tx_command(struct acmp *acmp, uint64_t now, const void *m, int len)
+{
+	return reply_not_supported(acmp, m, len);
+}
+
+static int handle_connect_tx_response(struct acmp *acmp, uint64_t now, const void *m, int len)
+{
+	struct server *server = acmp->server;
+	const struct avbtp_packet_acmp *resp = m;
+	struct avbtp_packet_acmp *reply;
+	struct pending *pending;
+	uint16_t sequence_id;
+	int res;
+
+	sequence_id = ntohs(resp->sequence_id);
+
+	pending = pending_find(acmp, PENDING_TALKER, sequence_id);
+	if (pending == NULL)
+		return 0;
+
+	reply = pending->ptr;
+	reply->sequence_id = htons(pending->old_sequence_id);
+	AVBTP_PACKET_ACMP_SET_MESSAGE_TYPE(reply, AVBTP_ACMP_MESSAGE_TYPE_CONNECT_RX_RESPONSE);
+	AVBTP_PACKET_ACMP_SET_STATUS(reply, AVBTP_PACKET_ACMP_GET_STATUS(resp));
+
+	res = avbtp_server_send_packet(server, reply->hdr.eth.dest, reply, pending->size);
+
+	pending_free(acmp, pending);
+
+	return res;
+}
+
+static int handle_disconnect_tx_command(struct acmp *acmp, uint64_t now, const void *m, int len)
+{
+	return reply_not_supported(acmp, m, len);
+}
+
+static int handle_disconnect_tx_response(struct acmp *acmp, uint64_t now, const void *m, int len)
+{
+	struct server *server = acmp->server;
+	const struct avbtp_packet_acmp *resp = m;
+	struct avbtp_packet_acmp *reply;
+	struct pending *pending;
+	uint16_t sequence_id;
+	int res;
+
+	sequence_id = ntohs(resp->sequence_id);
+
+	pending = pending_find(acmp, PENDING_TALKER, sequence_id);
+	if (pending == NULL)
+		return 0;
+
+	reply = pending->ptr;
+	reply->sequence_id = htons(pending->old_sequence_id);
+	AVBTP_PACKET_ACMP_SET_MESSAGE_TYPE(reply, AVBTP_ACMP_MESSAGE_TYPE_DISCONNECT_RX_RESPONSE);
+	AVBTP_PACKET_ACMP_SET_STATUS(reply, AVBTP_PACKET_ACMP_GET_STATUS(resp));
+
+	res = avbtp_server_send_packet(server, reply->hdr.eth.dest, reply, pending->size);
+
+	pending_free(acmp, pending);
+
+	return res;
+}
+
+static int handle_connect_rx_command(struct acmp *acmp, uint64_t now, const void *m, int len)
+{
+	struct server *server = acmp->server;
+	struct avbtp_packet_acmp *cmd;
+
+	cmd = pending_new(acmp, PENDING_TALKER, now,
+			AVBTP_ACMP_TIMEOUT_CONNECT_TX_COMMAND_MS, m, len);
+	if (cmd == NULL)
+		return -errno;
+
+	AVBTP_PACKET_ACMP_SET_MESSAGE_TYPE(cmd, AVBTP_ACMP_MESSAGE_TYPE_CONNECT_TX_COMMAND);
+	AVBTP_PACKET_ACMP_SET_STATUS(cmd, AVBTP_ACMP_STATUS_SUCCESS);
+
+	return avbtp_server_send_packet(server, cmd->hdr.eth.dest, cmd, len);
+}
+
+static int handle_connect_rx_response(struct acmp *acmp, uint64_t now, const void *p, int len)
+{
+	return reply_not_supported(acmp, p, len);
+}
+
+static int handle_disconnect_rx_command(struct acmp *acmp, uint64_t now, const void *m, int len)
+{
+	struct server *server = acmp->server;
+	struct avbtp_packet_acmp *cmd;
+
+	cmd = pending_new(acmp, PENDING_TALKER, now,
+			AVBTP_ACMP_TIMEOUT_DISCONNECT_TX_COMMAND_MS, m, len);
+	if (cmd == NULL)
+		return -errno;
+
+	AVBTP_PACKET_ACMP_SET_MESSAGE_TYPE(cmd, AVBTP_ACMP_MESSAGE_TYPE_DISCONNECT_TX_COMMAND);
+	AVBTP_PACKET_ACMP_SET_STATUS(cmd, AVBTP_ACMP_STATUS_SUCCESS);
+
+	return avbtp_server_send_packet(server, cmd->hdr.eth.dest, cmd, len);
+}
+
+static int handle_disconnect_rx_response(struct acmp *acmp, uint64_t now, const void *p, int len)
+{
+	return reply_not_supported(acmp, p, len);
+}
+
 static const struct msg_info msg_info[] = {
-	{ AVBTP_ACMP_MESSAGE_TYPE_CONNECT_TX_COMMAND, "connect-tx-command", NULL, },
-	{ AVBTP_ACMP_MESSAGE_TYPE_CONNECT_TX_RESPONSE, "connect-tx-response", NULL, },
-	{ AVBTP_ACMP_MESSAGE_TYPE_DISCONNECT_TX_COMMAND, "disconnect-tx-command", NULL, },
-	{ AVBTP_ACMP_MESSAGE_TYPE_DISCONNECT_TX_RESPONSE, "disconnect-tx-response", NULL, },
+	{ AVBTP_ACMP_MESSAGE_TYPE_CONNECT_TX_COMMAND, "connect-tx-command", handle_connect_tx_command, },
+	{ AVBTP_ACMP_MESSAGE_TYPE_CONNECT_TX_RESPONSE, "connect-tx-response", handle_connect_tx_response, },
+	{ AVBTP_ACMP_MESSAGE_TYPE_DISCONNECT_TX_COMMAND, "disconnect-tx-command", handle_disconnect_tx_command, },
+	{ AVBTP_ACMP_MESSAGE_TYPE_DISCONNECT_TX_RESPONSE, "disconnect-tx-response", handle_disconnect_tx_response, },
 	{ AVBTP_ACMP_MESSAGE_TYPE_GET_TX_STATE_COMMAND, "get-tx-state-command", NULL, },
 	{ AVBTP_ACMP_MESSAGE_TYPE_GET_TX_STATE_RESPONSE, "get-tx-state-response", NULL, },
-	{ AVBTP_ACMP_MESSAGE_TYPE_CONNECT_RX_COMMAND, "connect-rx-command", NULL, },
-	{ AVBTP_ACMP_MESSAGE_TYPE_CONNECT_RX_RESPONSE, "connect-rx-response", NULL, },
-	{ AVBTP_ACMP_MESSAGE_TYPE_DISCONNECT_RX_COMMAND, "disconnect-rx-command", NULL, },
-	{ AVBTP_ACMP_MESSAGE_TYPE_DISCONNECT_RX_RESPONSE, "disconnect-rx-response", NULL, },
+	{ AVBTP_ACMP_MESSAGE_TYPE_CONNECT_RX_COMMAND, "connect-rx-command", handle_connect_rx_command, },
+	{ AVBTP_ACMP_MESSAGE_TYPE_CONNECT_RX_RESPONSE, "connect-rx-response", handle_connect_rx_response, },
+	{ AVBTP_ACMP_MESSAGE_TYPE_DISCONNECT_RX_COMMAND, "disconnect-rx-command", handle_disconnect_rx_command, },
+	{ AVBTP_ACMP_MESSAGE_TYPE_DISCONNECT_RX_RESPONSE, "disconnect-rx-response", handle_disconnect_rx_response, },
 	{ AVBTP_ACMP_MESSAGE_TYPE_GET_RX_STATE_COMMAND, "get-rx-state-command", NULL, },
 	{ AVBTP_ACMP_MESSAGE_TYPE_GET_RX_STATE_RESPONSE, "get-rx-state-response", NULL, },
 	{ AVBTP_ACMP_MESSAGE_TYPE_GET_TX_CONNECTION_COMMAND, "get-tx-connection-command", NULL, },
@@ -102,7 +271,7 @@ static int acmp_message(void *data, uint64_t now, const void *message, int len)
 	if (info->handle == NULL)
 		return reply_not_supported(acmp, p, len);
 
-	return info->handle(acmp, p, len);
+	return info->handle(acmp, now, p, len);
 }
 
 static void acmp_destroy(void *data)
@@ -112,6 +281,31 @@ static void acmp_destroy(void *data)
 	free(acmp);
 }
 
+static void check_timeout(struct acmp *acmp, uint64_t now, uint16_t type)
+{
+	struct pending *p, *t;
+
+	spa_list_for_each_safe(p, t, &acmp->pending[type], link) {
+		if (p->last_time + p->timeout > now)
+			continue;
+
+		if (p->retry == 0) {
+			pw_log_info("%p: pending timeout, retry", p);
+			retry_pending(acmp, now, p);
+		} else {
+			pw_log_info("%p: pending timeout, fail", p);
+			pending_free(acmp, p);
+		}
+	}
+}
+static void acmp_periodic(void *data, uint64_t now)
+{
+	struct acmp *acmp = data;
+	check_timeout(acmp, now, PENDING_TALKER);
+	check_timeout(acmp, now, PENDING_LISTENER);
+	check_timeout(acmp, now, PENDING_CONTROLLER);
+}
+
 static int do_help(struct acmp *acmp, const char *args, FILE *out)
 {
 	fprintf(out, "{ \"type\": \"help\","
@@ -143,6 +337,7 @@ static const struct server_events server_events = {
 	AVBTP_VERSION_SERVER_EVENTS,
 	.destroy = acmp_destroy,
 	.message = acmp_message,
+	.periodic = acmp_periodic,
 	.command = acmp_command
 };
 
@@ -155,6 +350,9 @@ struct avbtp_acmp *avbtp_acmp_register(struct server *server)
 		return NULL;
 
 	acmp->server = server;
+	spa_list_init(&acmp->pending[PENDING_TALKER]);
+	spa_list_init(&acmp->pending[PENDING_LISTENER]);
+	spa_list_init(&acmp->pending[PENDING_CONTROLLER]);
 
 	avdecc_server_add_listener(server, &acmp->server_listener, &server_events, acmp);
 
diff --git a/src/modules/module-avbtp/acmp.h b/src/modules/module-avbtp/acmp.h
index ebef9dbbe..6fb218686 100644
--- a/src/modules/module-avbtp/acmp.h
+++ b/src/modules/module-avbtp/acmp.h
@@ -64,6 +64,14 @@
 #define AVBTP_ACMP_STATUS_LISTENER_INVALID_CONNECTION	18
 #define AVBTP_ACMP_STATUS_NOT_SUPPORTED			31
 
+#define AVBTP_ACMP_TIMEOUT_CONNECT_TX_COMMAND_MS	2000
+#define AVBTP_ACMP_TIMEOUT_DISCONNECT_TX_COMMAND_MS	200
+#define AVBTP_ACMP_TIMEOUT_GET_TX_STATE_COMMAND		200
+#define AVBTP_ACMP_TIMEOUT_CONNECT_RX_COMMAND_MS	4500
+#define AVBTP_ACMP_TIMEOUT_DISCONNECT_RX_COMMAND_MS	500
+#define AVBTP_ACMP_TIMEOUT_GET_RX_STATE_COMMAND_MS	200
+#define AVBTP_ACMP_TIMEOUT_GET_TX_CONNECTION_COMMAND	200
+
 struct avbtp_packet_acmp {
 	struct avbtp_packet_header hdr;
 	uint64_t stream_id;
diff --git a/src/modules/module-avbtp/adp.c b/src/modules/module-avbtp/adp.c
index 68b18e6e9..5bd27c65a 100644
--- a/src/modules/module-avbtp/adp.c
+++ b/src/modules/module-avbtp/adp.c
@@ -83,7 +83,7 @@ static int send_discover(struct adp *adp, uint64_t entity_id)
 	struct avbtp_packet_adp p;
 	spa_zero(p);
 	AVBTP_PACKET_SET_SUBTYPE(&p.hdr, AVBTP_SUBTYPE_ADP);
-	AVBTP_PACKET_SET_LENGTH(&p.hdr, AVBTP_ADP_DATA_LENGTH);
+	AVBTP_PACKET_SET_LENGTH(&p.hdr, AVBTP_ADP_CONTROL_DATA_LENGTH);
 	AVBTP_PACKET_ADP_SET_MESSAGE_TYPE(&p, AVBTP_ADP_MESSAGE_TYPE_ENTITY_DISCOVER);
 	p.entity_id = htonl(entity_id);
 	avbtp_server_broadcast_packet(adp->server, &p, sizeof(p));
@@ -100,7 +100,7 @@ static int adp_message(void *data, uint64_t now, const void *message, int len)
 	uint64_t entity_id;
 
 	if (AVBTP_PACKET_GET_SUBTYPE(&p->hdr) != AVBTP_SUBTYPE_ADP ||
-	    AVBTP_PACKET_GET_LENGTH(&p->hdr) != AVBTP_ADP_DATA_LENGTH)
+	    AVBTP_PACKET_GET_LENGTH(&p->hdr) < AVBTP_ADP_CONTROL_DATA_LENGTH)
 		return 0;
 
 	message_type = AVBTP_PACKET_ADP_GET_MESSAGE_TYPE(p);
@@ -228,7 +228,7 @@ static int check_advertise(struct adp *adp, uint64_t now)
 	e->last_time = now;
 
 	p = &e->packet;
-	AVBTP_PACKET_SET_LENGTH(&p->hdr, AVBTP_ADP_DATA_LENGTH);
+	AVBTP_PACKET_SET_LENGTH(&p->hdr, AVBTP_ADP_CONTROL_DATA_LENGTH);
 	AVBTP_PACKET_SET_SUBTYPE(&p->hdr, AVBTP_SUBTYPE_ADP);
 	AVBTP_PACKET_ADP_SET_MESSAGE_TYPE(p, AVBTP_ADP_MESSAGE_TYPE_ENTITY_AVAILABLE);
 	AVBTP_PACKET_ADP_SET_VALID_TIME(p, 10);
diff --git a/src/modules/module-avbtp/adp.h b/src/modules/module-avbtp/adp.h
index 62f5436d9..e30cf991b 100644
--- a/src/modules/module-avbtp/adp.h
+++ b/src/modules/module-avbtp/adp.h
@@ -72,7 +72,7 @@
 #define AVBTP_ADP_CONTROLLER_CAPABILITY_IMPLEMENTED			(1u<<0)
 #define AVBTP_ADP_CONTROLLER_CAPABILITY_LAYER3_PROXY			(1u<<1)
 
-#define AVBTP_ADP_DATA_LENGTH	56
+#define AVBTP_ADP_CONTROL_DATA_LENGTH		56
 
 struct avbtp_packet_adp {
 	struct avbtp_packet_header hdr;
diff --git a/src/modules/module-avbtp/avdecc.c b/src/modules/module-avbtp/avdecc.c
index 1f008e28d..d24b7d95b 100644
--- a/src/modules/module-avbtp/avdecc.c
+++ b/src/modules/module-avbtp/avdecc.c
@@ -39,6 +39,7 @@
 #include "avb.h"
 #include "packets.h"
 #include "internal.h"
+#include "acmp.h"
 #include "adp.h"
 #include "aecp.h"
 #include "maap.h"
diff --git a/src/modules/module-avbtp/internal.h b/src/modules/module-avbtp/internal.h
index 9bb67e210..5cf437d98 100644
--- a/src/modules/module-avbtp/internal.h
+++ b/src/modules/module-avbtp/internal.h
@@ -94,7 +94,7 @@ static inline const struct descriptor *server_find_descriptor(struct server *ser
 	}
 	return NULL;
 }
-static inline const struct descriptor *server_add_descriptor(struct server *server,
+static inline void *server_add_descriptor(struct server *server,
 		uint16_t type, uint16_t index, size_t size, void *ptr)
 {
 	struct descriptor *d;
@@ -106,9 +106,10 @@ static inline const struct descriptor *server_add_descriptor(struct server *serv
 	d->index = index;
 	d->size = size;
 	d->ptr = SPA_PTROFF(d, sizeof(struct descriptor), void);
-	memcpy(d->ptr, ptr, size);
+	if (ptr)
+		memcpy(d->ptr, ptr, size);
 	spa_list_append(&server->descriptors, &d->link);
-	return d;
+	return d->ptr;
 }
 
 struct server *avdecc_server_new(struct impl *impl, const char *ifname, struct spa_dict *props);