diff --git a/multimedia/vapoursynth-l-smash-works/Makefile b/multimedia/vapoursynth-l-smash-works/Makefile
index b99efe0e89ac..4a9ce5d9d90a 100644
--- a/multimedia/vapoursynth-l-smash-works/Makefile
+++ b/multimedia/vapoursynth-l-smash-works/Makefile
@@ -1,62 +1,64 @@
 PORTNAME=	l-smash-works
 DISTVERSION=	0.0-940 # git rev-list --count HEAD
 DISTVERSIONSUFFIX=	-g198cc78
 PORTREVISION=	1
 CATEGORIES=	multimedia
 PKGNAMEPREFIX=	vapoursynth-
 
 MAINTAINER=	jbeich@FreeBSD.org
 COMMENT=	L-SMASH source plugin for VapourSynth
 WWW=		https://github.com/VFR-maniac/L-SMASH-Works/tree/master/VapourSynth
 
 LICENSE=	ISCL
 LICENSE_FILE=	${WRKSRC}/LICENSE
 
+BROKEN=		fails to build with FFmpeg 6 (PR 270303)
+
 BUILD_DEPENDS=	${LOCALBASE}/include/vapoursynth/VSHelper.h:multimedia/vapoursynth
 BUILD_DEPENDS+=	ffmpeg>=3.2,1:multimedia/ffmpeg
 LIB_DEPENDS=	libavcodec.so:multimedia/ffmpeg \
 		liblsmash.so:multimedia/l-smash
 
 USE_GITHUB=	yes
 GH_ACCOUNT=	VFR-maniac
 GH_PROJECT=	L-SMASH-Works
 
 USES=		gmake pkgconfig shebangfix
 EXCLUDE=	VSHelper.h VSScript.h VapourSynth.h
 EXTRACT_AFTER_ARGS=${EXCLUDE:S,^,--exclude ,}
 WRKSRC_SUBDIR=	VapourSynth
 SHEBANG_FILES=	configure
 bash_CMD=	${SH}
 HAS_CONFIGURE=	yes
 CONFIGURE_ENV=	LD="${CC}" REV="${PORTVERSION:E}" \
 		HASH="${DISTVERSIONSUFFIX:S/^-g//}"
 CONFIGURE_ARGS=	--prefix="${PREFIX}" \
 		--extra-cflags="${CPPFLAGS} ${CFLAGS}" \
 		--extra-ldflags="${LDFLAGS}" \
 		--extra-libs="${LIBS}"
 MAKEFILE=	GNUmakefile
 MAKE_ARGS=	STRIP="${STRIP_CMD}"
 CPPFLAGS+=	`pkg-config vapoursynth --cflags`
 USE_LDCONFIG=	yes
 DATADIR=	${PREFIX}/lib/vapoursynth
 DOCSDIR=	${PREFIX}/share/doc/${PKGBASE}
 PLIST_FILES=	lib/libvslsmashsource.so.${PORTVERSION:E}
 PORTDATA=	libvslsmashsource.so
 PORTDOCS=	README
 
 OPTIONS_DEFINE=	DOCS
 
 post-patch:
 	@${REINPLACE_CMD} -Ee '/CROSS/!s/^(CC|LD|REV|HASH)=.*/: $${&}/' \
 		-e 's/pushd/cd/; s/popd/cd -/' \
 		-e 's/-Os //; /=.*-fexcess-precision/d' \
 		${WRKSRC}/configure
 	@${REINPLACE_CMD} 's/ -msse2 -g0//' ${WRKSRC}/${MAKEFILE}
 
 post-install:
 	${RLN} ${STAGEDIR}${PREFIX}/lib/libvslsmashsource.so.${PORTVERSION:E} \
 		${STAGEDIR}${DATADIR}/libvslsmashsource.so
 	(cd ${WRKSRC} && ${COPYTREE_SHARE} \
 		"${PORTDOCS}" ${STAGEDIR}${DOCSDIR})
 
 .include <bsd.port.mk>