diff --git a/libfwupdplugin/fu-srec-firmware.c b/libfwupdplugin/fu-srec-firmware.c
index 1382021b6..5a6071bf2 100644
--- a/libfwupdplugin/fu-srec-firmware.c
+++ b/libfwupdplugin/fu-srec-firmware.c
@@ -550,11 +550,9 @@ fu_srec_firmware_write(FuFirmware *firmware, GError **error)
 	/* upgrade to longer addresses? */
 	if (fu_firmware_get_addr(firmware) >= (1ull << 24)) {
 		kind_data = FU_FIRMWARE_SREC_RECORD_KIND_S3_DATA_32;
-		kind_coun = FU_FIRMWARE_SREC_RECORD_KIND_S6_COUNT_24;
 		kind_term = FU_FIRMWARE_SREC_RECORD_KIND_S7_COUNT_32; /* intentional... */
 	} else if (fu_firmware_get_addr(firmware) >= (1ull << 16)) {
 		kind_data = FU_FIRMWARE_SREC_RECORD_KIND_S2_DATA_24;
-		kind_coun = FU_FIRMWARE_SREC_RECORD_KIND_S6_COUNT_24;
 		kind_term = FU_FIRMWARE_SREC_RECORD_KIND_S8_TERMINATION_24;
 	}
 
@@ -585,6 +583,9 @@ fu_srec_firmware_write(FuFirmware *firmware, GError **error)
 						    fu_chunk_get_data(chk),
 						    fu_chunk_get_data_sz(chk));
 		}
+		/* upgrade to longer format */
+		if (chunks->len > G_MAXUINT16)
+			kind_coun = FU_FIRMWARE_SREC_RECORD_KIND_S6_COUNT_24;
 		fu_srec_firmware_write_line(str, kind_coun, chunks->len, NULL, 0);
 	}
 
diff --git a/plugins/wacom-usb/fu-self-test.c b/plugins/wacom-usb/fu-self-test.c
index cca19b39e..3359391a8 100644
--- a/plugins/wacom-usb/fu-self-test.c
+++ b/plugins/wacom-usb/fu-self-test.c
@@ -73,7 +73,7 @@ fu_wac_firmware_xml_func(void)
 	g_assert_true(ret);
 	csum1 = fu_firmware_get_checksum(firmware1, G_CHECKSUM_SHA1, &error);
 	g_assert_no_error(error);
-	g_assert_cmpstr(csum1, ==, "bd734911430831127a7bba4664e212a56a2821bc");
+	g_assert_cmpstr(csum1, ==, "346f6196449b356777cf241f6edb039d503b88a1");
 
 	/* ensure we can round-trip */
 	xml_out = fu_firmware_export_to_xml(firmware1, FU_FIRMWARE_EXPORT_FLAG_NONE, &error);