diff --git a/src/main/msp/msp_server_fc.c b/src/main/msp/msp_server_fc.c
index 919f30247..260d6ed6e 100755
--- a/src/main/msp/msp_server_fc.c
+++ b/src/main/msp/msp_server_fc.c
@@ -429,10 +429,11 @@ static void serializeDataflashReadReply(uint32_t address, uint16_t size, bool us
 
         serialize32(address);
     } else {
-        headSerialReply(sizeof(uint32_t) + sizeof(uint16_t) + bytesRead);
+        headSerialReply(sizeof(uint32_t) + sizeof(uint16_t) + sizeof(uint8_t) + bytesRead);
 
         serialize32(address);
         serialize16(bytesRead);
+        serialize8(0); // placeholder for compression format
     }
 
     int i;