---- a/source/encoder/encoder.cpp
-+++ b/source/encoder/encoder.cpp
-@@ -1330,6 +1330,12 @@
- p->bBPyramid = 0;
-
- /* Disable features which are not supported by the current RD level */
-+ if (p->rdLevel < 5)
-+ {
-+ if (p->bEnableCbfFastMode) /* impossible */
-+ x265_log(p, X265_LOG_WARNING, "--fast-cbf disabled, requires --rdlevel 5 or higher\n");
-+ p->bEnableCbfFastMode = 0;
-+ }
- if (p->rdLevel < 4)
- {
- if (p->psyRdoq > 0) /* impossible */