diff --git a/source/event-emitter.ts b/source/event-emitter.ts
index 857f9c4..5ea4070 100644
--- a/source/event-emitter.ts
+++ b/source/event-emitter.ts
@@ -57,9 +57,13 @@ export class EventEmitter<T extends EventMap> {
         const listenerEntry: ListenerEntry<T[K]> = {
             listener,
             wrappedListener,
-            ...(debounceMilliseconds !== undefined ? { debounceTime: debounceMilliseconds } : {}),
         };
 
+        // Set the debounce time if specified.
+        if (debounceMilliseconds && debounceMilliseconds > 0) {
+            listenerEntry.debounceTime = debounceMilliseconds;
+        }
+
         // Add the listener entry to the listeners map.
         this.#listeners.get(type)?.add(listenerEntry);
 
@@ -94,9 +98,13 @@ export class EventEmitter<T extends EventMap> {
             listener,
             wrappedListener: debouncedListener,
             once: true,
-            ...(debounceMilliseconds !== undefined ? { debounceTime: debounceMilliseconds } : {}),
         };
 
+        // Set the debounce time if specified.
+        if (debounceMilliseconds && debounceMilliseconds > 0) {
+            listenerEntry.debounceTime = debounceMilliseconds;
+        }
+
         // Add the listener entry to the listeners map.
         this.#listeners.get(type)?.add(listenerEntry);