diff --git a/Machines/MasterSystem/MasterSystem.cpp b/Machines/MasterSystem/MasterSystem.cpp
index 30c20e672..8136049f6 100644
--- a/Machines/MasterSystem/MasterSystem.cpp
+++ b/Machines/MasterSystem/MasterSystem.cpp
@@ -181,24 +181,27 @@ template <Analyser::Static::Sega::Target::Model model> class ConcreteMachine:
 		}
 
 		void set_scan_target(Outputs::Display::ScanTarget *scan_target) final {
-			vdp_->set_tv_standard(
+			vdp_.last_valid()->set_tv_standard(
 				(region_ == Target::Region::Europe) ?
 					TI::TMS::TVStandard::PAL : TI::TMS::TVStandard::NTSC);
-			time_until_debounce_ = vdp_->get_time_until_line(-1);
 
-			vdp_->set_scan_target(scan_target);
+			// Doing the following would be technically correct, but isn't
+			// especially thread-safe and won't make a substantial difference.
+//			time_until_debounce_ = vdp_->get_time_until_line(-1);
+
+			vdp_.last_valid()->set_scan_target(scan_target);
 		}
 
 		Outputs::Display::ScanStatus get_scaled_scan_status() const final {
-			return vdp_->get_scaled_scan_status();
+			return vdp_.last_valid()->get_scaled_scan_status();
 		}
 
 		void set_display_type(Outputs::Display::DisplayType display_type) final {
-			vdp_->set_display_type(display_type);
+			vdp_.last_valid()->set_display_type(display_type);
 		}
 
 		Outputs::Display::DisplayType get_display_type() const final {
-			return vdp_->get_display_type();
+			return vdp_.last_valid()->get_display_type();
 		}
 
 		Outputs::Speaker::Speaker *get_speaker() final {