diff --git a/spa/plugins/support/loop.c b/spa/plugins/support/loop.c
index 07e0bffff..17abad226 100644
--- a/spa/plugins/support/loop.c
+++ b/spa/plugins/support/loop.c
@@ -85,6 +85,7 @@ struct impl {
 
 	struct spa_ratelimit rate_limit;
 	int retry_timeout;
+	bool prio_inherit;
 
 	union tag head;
 
@@ -1371,9 +1372,6 @@ impl_init(const struct spa_handle_factory *factory,
 			SPA_VERSION_LOOP_UTILS,
 			&impl_loop_utils, impl);
 
-	CHECK(pthread_mutexattr_init(&attr), error_exit);
-	CHECK(pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE), error_exit_free_attr);
-
 	impl->rate_limit.interval = 2 * SPA_NSEC_PER_SEC;
 	impl->rate_limit.burst = 1;
 	impl->retry_timeout = DEFAULT_RETRY;
@@ -1383,13 +1381,15 @@ impl_init(const struct spa_handle_factory *factory,
 			impl->control.iface.cb.funcs = &impl_loop_control_cancel;
 		if ((str = spa_dict_lookup(info, "loop.retry-timeout")) != NULL)
 			impl->retry_timeout = atoi(str);
-		if ((str = spa_dict_lookup(info, "loop.prio-inherit")) != NULL &&
-		    spa_atob(str)) {
-			CHECK(pthread_mutexattr_setprotocol(&attr, PTHREAD_PRIO_INHERIT),
-					error_exit_free_attr)
-		}
+		if ((str = spa_dict_lookup(info, "loop.prio-inherit")) != NULL)
+			impl->prio_inherit = spa_atob(str);
 	}
 
+	CHECK(pthread_mutexattr_init(&attr), error_exit);
+	CHECK(pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE), error_exit_free_attr);
+	if (impl->prio_inherit)
+		CHECK(pthread_mutexattr_setprotocol(&attr, PTHREAD_PRIO_INHERIT),
+					error_exit_free_attr)
 	CHECK(pthread_mutex_init(&impl->lock, &attr), error_exit_free_attr);
 	pthread_mutexattr_destroy(&attr);
 
diff --git a/spa/plugins/support/node-driver.c b/spa/plugins/support/node-driver.c
index c8777caa3..701a5b7bf 100644
--- a/spa/plugins/support/node-driver.c
+++ b/spa/plugins/support/node-driver.c
@@ -280,7 +280,7 @@ static int reassign_follower(struct impl *this)
 	if (following != this->following) {
 		spa_log_debug(this->log, "%p: reassign follower %d->%d", this, this->following, following);
 		this->following = following;
-		spa_loop_invoke(this->data_loop, do_set_timers, 0, NULL, 0, true, this);
+		spa_loop_locked(this->data_loop, do_set_timers, 0, NULL, 0, this);
 	}
 	return 0;
 }
@@ -431,7 +431,7 @@ static int do_start(struct impl *this)
 	this->following = is_following(this);
 	this->started = true;
 	this->last_time = 0;
-	spa_loop_invoke(this->data_loop, do_set_timers, 0, NULL, 0, true, this);
+	spa_loop_locked(this->data_loop, do_set_timers, 0, NULL, 0, this);
 	return 0;
 }
 
@@ -440,7 +440,7 @@ static int do_stop(struct impl *this)
 	if (!this->started)
 		return 0;
 	this->started = false;
-	spa_loop_invoke(this->data_loop, do_set_timers, 0, NULL, 0, true, this);
+	spa_loop_locked(this->data_loop, do_set_timers, 0, NULL, 0, this);
 	return 0;
 }
 
@@ -573,7 +573,7 @@ static int impl_clear(struct spa_handle *handle)
 
 	this = (struct impl *) handle;
 
-	spa_loop_invoke(this->data_loop, do_remove_timer, 0, NULL, 0, true, this);
+	spa_loop_locked(this->data_loop, do_remove_timer, 0, NULL, 0, this);
 	spa_system_close(this->data_system, this->timer_source.fd);
 
 	if (this->clock_fd != -1)
diff --git a/spa/plugins/support/null-audio-sink.c b/spa/plugins/support/null-audio-sink.c
index 997a66810..70edd4ff2 100644
--- a/spa/plugins/support/null-audio-sink.c
+++ b/spa/plugins/support/null-audio-sink.c
@@ -230,7 +230,7 @@ static int reassign_follower(struct impl *this)
 	if (following != this->following) {
 		spa_log_debug(this->log, "%p: reassign follower %d->%d", this, this->following, following);
 		this->following = following;
-		spa_loop_invoke(this->data_loop, do_set_timers, 0, NULL, 0, true, this);
+		spa_loop_locked(this->data_loop, do_set_timers, 0, NULL, 0, this);
 	}
 	return 0;
 }
@@ -314,7 +314,7 @@ static int do_start(struct impl *this)
 
 	this->following = is_following(this);
 	this->started = true;
-	spa_loop_invoke(this->data_loop, do_set_timers, 0, NULL, 0, true, this);
+	spa_loop_locked(this->data_loop, do_set_timers, 0, NULL, 0, this);
 	return 0;
 }
 
@@ -323,7 +323,7 @@ static int do_stop(struct impl *this)
 	if (!this->started)
 		return 0;
 	this->started = false;
-	spa_loop_invoke(this->data_loop, do_set_timers, 0, NULL, 0, true, this);
+	spa_loop_locked(this->data_loop, do_set_timers, 0, NULL, 0, this);
 	return 0;
 }
 
@@ -847,7 +847,7 @@ static int impl_clear(struct spa_handle *handle)
 
 	this = (struct impl *) handle;
 
-	spa_loop_invoke(this->data_loop, do_remove_timer, 0, NULL, 0, true, this);
+	spa_loop_locked(this->data_loop, do_remove_timer, 0, NULL, 0, this);
 	spa_system_close(this->data_system, this->timer_source.fd);
 
 	return 0;
diff --git a/spa/plugins/v4l2/v4l2-utils.c b/spa/plugins/v4l2/v4l2-utils.c
index 887094eff..58758f758 100644
--- a/spa/plugins/v4l2/v4l2-utils.c
+++ b/spa/plugins/v4l2/v4l2-utils.c
@@ -1928,7 +1928,7 @@ static int spa_v4l2_stream_off(struct impl *this)
 
 	spa_log_debug(this->log, "stopping");
 
-	spa_loop_invoke(this->data_loop, do_remove_source, 0, NULL, 0, true, port);
+	spa_loop_locked(this->data_loop, do_remove_source, 0, NULL, 0, port);
 
 	type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
 	if (xioctl(dev->fd, VIDIOC_STREAMOFF, &type) < 0) {