diff --git a/CHANGELOG.md b/CHANGELOG.md
index eddb5de4..9b9f3416 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,8 @@ In this document, Mod is Ctrl on Windows/Linux and Cmd on Mac.
 - Swap order of tags and brands in Module Browser.
 - Disable smoothing for MIDI CC buttons in MIDI-Map.
 - Automatically unzip update on Mac.
+- Core
+	- Fix sustain pedal release bug when using polyphonic mode in MIDI-CV.
 - API
 	- Add libsamplerate library.
 
diff --git a/src/engine/Engine.cpp b/src/engine/Engine.cpp
index 82c22915..ee0e64b8 100644
--- a/src/engine/Engine.cpp
+++ b/src/engine/Engine.cpp
@@ -429,12 +429,12 @@ static void Engine_run(Engine* that) {
 			aheadTime = 0.0;
 		}
 
-		// Launch workers
-		if (internal->threadCount != settings::threadCount || internal->realTime != settings::realTime) {
-			Engine_relaunchWorkers(that, settings::threadCount, settings::realTime);
-		}
-
 		if (!internal->paused) {
+			// Launch workers
+			if (internal->threadCount != settings::threadCount || internal->realTime != settings::realTime) {
+				Engine_relaunchWorkers(that, settings::threadCount, settings::realTime);
+			}
+
 			std::lock_guard<std::recursive_mutex> lock(internal->mutex);
 
 			// Update expander pointers
@@ -448,6 +448,12 @@ static void Engine_run(Engine* that) {
 				Engine_step(that);
 			}
 		}
+		else {
+			// Stop workers while closed
+			if (internal->threadCount != 1) {
+				Engine_relaunchWorkers(that, 1, settings::realTime);
+			}
+		}
 
 		double stepTime = mutexSteps * internal->sampleTime;
 		aheadTime += stepTime;