diff --git a/libs/ardour/ardour/rc_configuration_vars.h b/libs/ardour/ardour/rc_configuration_vars.h
index f58ae85bba..d476d557b8 100644
--- a/libs/ardour/ardour/rc_configuration_vars.h
+++ b/libs/ardour/ardour/rc_configuration_vars.h
@@ -223,6 +223,7 @@ CONFIG_VARIABLE (bool, allow_special_bus_removal, "allow-special-bus-removal", f
 CONFIG_VARIABLE (int32_t, processor_usage, "processor-usage", -1)
 CONFIG_VARIABLE (int32_t, cpu_dma_latency, "cpu-dma-latency", -1) /* >=0 to enable */
 CONFIG_VARIABLE (int32_t, io_thread_count, "io-thread-count", -2)
+CONFIG_VARIABLE (int32_t, io_thread_policy, "io-thread-policy", 0)
 CONFIG_VARIABLE (gain_t, max_gain, "max-gain", 2.0) /* +6.0dB */
 CONFIG_VARIABLE (uint32_t, max_recent_sessions, "max-recent-sessions", 10)
 CONFIG_VARIABLE (uint32_t, max_recent_templates, "max-recent-templates", 10)
diff --git a/libs/ardour/io_tasklist.cc b/libs/ardour/io_tasklist.cc
index 5e815c5faa..6fa338cbda 100644
--- a/libs/ardour/io_tasklist.cc
+++ b/libs/ardour/io_tasklist.cc
@@ -32,6 +32,7 @@
 #include "ardour/disk_reader.h"
 #include "ardour/io_tasklist.h"
 #include "ardour/process_thread.h"
+#include "ardour/rc_configuration.h"
 #include "ardour/session_event.h"
 
 #include "pbd/i18n.h"
@@ -50,54 +51,41 @@ IOTaskList::IOTaskList (uint32_t n_threads)
 		return;
 	}
 
-	pthread_attr_t     attr;
-	struct sched_param parm;
+	bool use_rt;
+	int  policy;
 
-  pthread_attr_init (&attr);
-
-	bool use_sched_param = true;
-	int  policy          = SCHED_RR;
-
-	const char* p = getenv ("ARDOUR_IO_SCHED");
-	if (p) {
-		int pi = atoi (p);
-		if (pi < 0) {
-			policy = SCHED_RR;
-		} else if (pi > 0) {
+	switch (Config->get_io_thread_policy ()) {
+		case 1:
+			use_rt = true;
 			policy = SCHED_FIFO;
-		} else {
-			use_sched_param = false;
-		}
+			break;
+		case 2:
+			use_rt = true;
+			policy = SCHED_RR;
+		default:
+			use_rt = false;
+			policy = SCHED_OTHER;
+			break;
 	}
 
-	if (use_sched_param) {
-		parm.sched_priority = pbd_absolute_rt_priority (SCHED_RR, pbd_pthread_priority (THREAD_IO));
 #ifdef PLATFORM_WINDOWS
-		pthread_attr_setschedpolicy (&attr, SCHED_OTHER);
-#else
-		pthread_attr_setschedpolicy (&attr, policy);
+	policy = SCHED_OTHER;
 #endif
-		pthread_attr_setschedparam (&attr, &parm);
-		pthread_attr_setscope (&attr, PTHREAD_SCOPE_SYSTEM);
-		pthread_attr_setinheritsched (&attr, PTHREAD_EXPLICIT_SCHED);
-		DEBUG_TRACE (PBD::DEBUG::IOTaskList, string_compose ("IOTaskList starting %1 threads with priority = %2, policy = %3\n", _n_threads, parm.sched_priority, policy));
-	} else {
-		DEBUG_TRACE (PBD::DEBUG::IOTaskList, string_compose ("IOTaskList starting %1 threads with default priority.\n", _n_threads));
-	}
+
+	DEBUG_TRACE (PBD::DEBUG::IOTaskList, string_compose ("IOTaskList starting %1 threads with sched policy = %2\n", _n_threads, policy));
 
 	_workers.resize (_n_threads);
 	for (uint32_t i = 0; i < _n_threads; ++i) {
-		if (pthread_create (&_workers[i], &attr, &_worker_thread, this)) {
-			if (pthread_create (&_workers[i], NULL, &_worker_thread, this)) {
+		if (!use_rt || pbd_realtime_pthread_create (policy, THREAD_IO, 0, &_workers[i], &_worker_thread, this)) {
+			if (use_rt && i == 0) {
+				PBD::warning << _("IOTaskList: cannot acquire realtime permissions.") << endmsg;
+			}
+			if (pbd_pthread_create (0, &_workers[i], &_worker_thread, this)) {
 				std::cerr << "Failed to start IOTaskList thread\n";
 				throw failed_constructor ();
 			}
-			if (i == 0) {
-				PBD::warning << _("IOTaskList: cannot acquire realtime permissions.") << endmsg;
-			}
 		}
 	}
-	pthread_attr_destroy (&attr);
 }
 
 IOTaskList::~IOTaskList ()