diff --git a/lib/speech2device.js b/lib/speech2device.js
index 0b64d9e..a8b40d5 100644
--- a/lib/speech2device.js
+++ b/lib/speech2device.js
@@ -280,9 +280,9 @@ class Speech2Device {
                 let count = 0;
                 let intervalHandler = setInterval(async () => {
                     count++;
-					// We are checking every 500 ms, expected length of playback is defined in variable duration in seconds
-					// Thus, we have to count to duration*2 to be able to wait long enough for the expected playback duration.
-					// We add two additional seconds, to cover delays before the playback starts.
+                    // We are checking every 500 ms, expected length of playback is defined in variable duration in seconds
+                    // Thus, we have to count to duration*2 to be able to wait long enough for the expected playback duration.
+                    // We add two additional seconds, to cover delays before the playback starts.
                     if (count > (duration+2)*2) {
                         clearInterval(intervalHandler);
                         intervalHandler = null;