diff --git a/armsrc/cmd.c b/armsrc/cmd.c
index 61ceda2f0..c7f76960b 100644
--- a/armsrc/cmd.c
+++ b/armsrc/cmd.c
@@ -43,7 +43,7 @@ bool reply_via_fpc = false;
 bool reply_via_usb = false;
 
 int reply_old(uint64_t cmd, uint64_t arg0, uint64_t arg1, uint64_t arg2, void *data, size_t len) {
-    PacketResponseOLD txcmd = {0};
+    PacketResponseOLD txcmd = {CMD_UNKNOWN, {0, 0, 0}, {{0}}};
 
 //    for (size_t i = 0; i < sizeof(PacketResponseOLD); i++)
 //        ((uint8_t *)&txcmd)[i] = 0x00;