diff --git a/library/src/SPSApplication.ts b/library/src/SPSApplication.ts
index 5d0f328f..4262ef5e 100644
--- a/library/src/SPSApplication.ts
+++ b/library/src/SPSApplication.ts
@@ -61,7 +61,7 @@ export class SPSApplication extends Application {
 		this.stream.setSignallingUrlBuilder(() => {
 
 			// if we have overriden the signalling server URL with a .env file use it here
-			if (WEBSOCKET_URL) {
+			if (WEBSOCKET_URL !== undefined) {
 				return WEBSOCKET_URL as string;
 			}