diff --git a/subprojects/gst-plugins-base/gst-libs/gst/rtp/gstrtpbasepayload.c b/subprojects/gst-plugins-base/gst-libs/gst/rtp/gstrtpbasepayload.c
index 648b34e153..4939001db7 100644
--- a/subprojects/gst-plugins-base/gst-libs/gst/rtp/gstrtpbasepayload.c
+++ b/subprojects/gst-plugins-base/gst-libs/gst/rtp/gstrtpbasepayload.c
@@ -114,7 +114,7 @@ static guint gst_rtp_base_payload_signals[LAST_SIGNAL] = { 0 };
 #define DEFAULT_AUTO_HEADER_EXTENSION   TRUE
 
 #define RTP_HEADER_EXT_ONE_BYTE_MAX_SIZE 16
-#define RTP_HEADER_EXT_TWO_BYTE_MAX_SIZE 256
+#define RTP_HEADER_EXT_TWO_BYTE_MAX_SIZE 255
 #define RTP_HEADER_EXT_ONE_BYTE_MAX_ID 14
 #define RTP_HEADER_EXT_TWO_BYTE_MAX_ID 255