diff --git a/Components/1770/1770.cpp b/Components/1770/1770.cpp
index 00f6220b6..081cf3956 100644
--- a/Components/1770/1770.cpp
+++ b/Components/1770/1770.cpp
@@ -769,16 +769,18 @@ void WD1770::posit_event(int new_event_type) {
 }
 
 void WD1770::update_status(std::function<void(Status &)> updater) {
+	const Status old_status = status_;
+
 	if(delegate_) {
-		Status old_status = status_;
 		updater(status_);
 		const bool did_change =
 			(status_.busy != old_status.busy) ||
 			(status_.data_request != old_status.data_request) ||
 			(status_.interrupt_request != old_status.interrupt_request);
 		if(did_change) delegate_->wd1770_did_change_output(this);
-	}
-	else updater(status_);
+	} else updater(status_);
+
+	if(status_.busy != old_status.busy) update_clocking_observer();
 }
 
 void WD1770::set_head_load_request(bool head_load) {}
@@ -788,3 +790,8 @@ void WD1770::set_head_loaded(bool head_loaded) {
 	head_is_loaded_ = head_loaded;
 	if(head_loaded) posit_event(static_cast<int>(Event1770::HeadLoad));
 }
+
+ClockingHint::Preference WD1770::preferred_clocking() {
+	if(status_.busy) return ClockingHint::Preference::RealTime;
+	return Storage::Disk::MFMController::preferred_clocking();
+}
diff --git a/Components/1770/1770.hpp b/Components/1770/1770.hpp
index 04a71a09a..35e349b10 100644
--- a/Components/1770/1770.hpp
+++ b/Components/1770/1770.hpp
@@ -73,6 +73,8 @@ class WD1770: public Storage::Disk::MFMController {
 		};
 		inline void set_delegate(Delegate *delegate)	{	delegate_ = delegate;			}
 
+		ClockingHint::Preference preferred_clocking() final;
+
 	protected:
 		virtual void set_head_load_request(bool head_load);
 		virtual void set_motor_on(bool motor_on);
diff --git a/Machines/AtariST/AtariST.cpp b/Machines/AtariST/AtariST.cpp
index 338ea7283..a18de827e 100644
--- a/Machines/AtariST/AtariST.cpp
+++ b/Machines/AtariST/AtariST.cpp
@@ -279,6 +279,7 @@ class ConcreteMachine:
 			keyboard_acia_->set_clocking_hint_observer(this);
 			ikbd_.set_clocking_hint_observer(this);
 			mfp_->set_clocking_hint_observer(this);
+			dma_->set_clocking_hint_observer(this);
 
 			mfp_->set_interrupt_delegate(this);
 			dma_->set_interrupt_delegate(this);
@@ -658,6 +659,7 @@ class ConcreteMachine:
 				(midi_acia_.last_valid()->preferred_clocking() != ClockingHint::Preference::RealTime);
 			keyboard_needs_clock_ = ikbd_.preferred_clocking() != ClockingHint::Preference::None;
 			mfp_is_realtime_ = mfp_.last_valid()->preferred_clocking() == ClockingHint::Preference::RealTime;
+			dma_is_realtime_ = dma_.last_valid()->preferred_clocking() == ClockingHint::Preference::RealTime;
 		}
 
 		// MARK: - GPIP input.
diff --git a/Machines/AtariST/DMAController.cpp b/Machines/AtariST/DMAController.cpp
index 45522f4dd..46ba8865e 100644
--- a/Machines/AtariST/DMAController.cpp
+++ b/Machines/AtariST/DMAController.cpp
@@ -14,6 +14,7 @@ using namespace Atari::ST;
 
 DMAController::DMAController() {
 	fdc_.set_delegate(this);
+	fdc_.set_clocking_hint_observer(this);
 }
 
 uint16_t DMAController::read(int address) {
@@ -100,3 +101,11 @@ void DMAController::set_interrupt_delegate(InterruptDelegate *delegate) {
 bool DMAController::get_interrupt_line() {
 	return interrupt_line_;
 }
+
+void DMAController::set_component_prefers_clocking(ClockingHint::Source *, ClockingHint::Preference) {
+	update_clocking_observer();
+}
+
+ClockingHint::Preference DMAController::preferred_clocking() {
+	return (fdc_.preferred_clocking() == ClockingHint::Preference::None) ? ClockingHint::Preference::None : ClockingHint::Preference::RealTime;
+}
diff --git a/Machines/AtariST/DMAController.hpp b/Machines/AtariST/DMAController.hpp
index 59cacdd3b..cbedc18ed 100644
--- a/Machines/AtariST/DMAController.hpp
+++ b/Machines/AtariST/DMAController.hpp
@@ -13,12 +13,13 @@
 #include <vector>
 
 #include "../../ClockReceiver/ClockReceiver.hpp"
+#include "../../ClockReceiver/ClockingHintSource.hpp"
 #include "../../Components/1770/1770.hpp"
 
 namespace Atari {
 namespace ST {
 
-class DMAController: public WD::WD1770::Delegate {
+class DMAController: public WD::WD1770::Delegate, public ClockingHint::Source, public ClockingHint::Observer {
 	public:
 		DMAController();
 
@@ -33,6 +34,9 @@ class DMAController: public WD::WD1770::Delegate {
 		};
 		void set_interrupt_delegate(InterruptDelegate *delegate);
 
+		// ClockingHint::Source.
+		ClockingHint::Preference preferred_clocking() final;
+
 	private:
 		HalfCycles running_time_;
 		struct WD1772: public WD::WD1770 {
@@ -59,6 +63,8 @@ class DMAController: public WD::WD1770::Delegate {
 
 		InterruptDelegate *interrupt_delegate_ = nullptr;
 		bool interrupt_line_ = false;
+
+		void set_component_prefers_clocking(ClockingHint::Source *, ClockingHint::Preference) final;
 };
 
 }