diff --git a/src/hci.h b/src/hci.h
index 84b5818d6..f4bd66f94 100644
--- a/src/hci.h
+++ b/src/hci.h
@@ -158,12 +158,13 @@ extern "C" {
     #endif
 #endif
 
-// BNEP may uncompress the IP Header by 16 bytes, GATT Client requires two additional bytes for long characteristic reads
+// BNEP may uncompress the IP Header by 16 bytes, GATT Client requires six additional bytes for long characteristic reads
+// wih service_id + connection_id
 #ifndef HCI_INCOMING_PRE_BUFFER_SIZE
 #ifdef ENABLE_CLASSIC
 #define HCI_INCOMING_PRE_BUFFER_SIZE (16 - HCI_ACL_HEADER_SIZE - 4)
 #else
-#define HCI_INCOMING_PRE_BUFFER_SIZE 2
+#define HCI_INCOMING_PRE_BUFFER_SIZE 6
 #endif
 #endif