diff --git a/usermods/audioreactive/audio_reactive.h b/usermods/audioreactive/audio_reactive.h
index 692714ec..215ec6e9 100644
--- a/usermods/audioreactive/audio_reactive.h
+++ b/usermods/audioreactive/audio_reactive.h
@@ -960,6 +960,8 @@ class AudioReactive : public Usermod {
       //DEBUGSR_PRINTLN("Transmitting UDP Mic Packet");
 
       audioSyncPacket transmitData;
+      memset(reinterpret_cast<void *>(&transmitData), 0, sizeof(transmitData)); // make sure that the packet - including "invisible" padding bytes added by the compiler - is fully initialized
+
       strncpy_P(transmitData.header, PSTR(UDP_SYNC_HEADER), 6);
       // transmit samples that were not modified by limitSampleDynamics()
       transmitData.sampleRaw   = (soundAgc) ? rawSampleAgc: sampleRaw;