diff --git a/src/decoder/plugins/FfmpegDecoderPlugin.cxx b/src/decoder/plugins/FfmpegDecoderPlugin.cxx
index f9915554a..773cf071a 100644
--- a/src/decoder/plugins/FfmpegDecoderPlugin.cxx
+++ b/src/decoder/plugins/FfmpegDecoderPlugin.cxx
@@ -471,7 +471,7 @@ static bool
 IsSeekable(const AVFormatContext &format_context) noexcept
 {
 #if LIBAVFORMAT_VERSION_INT >= AV_VERSION_INT(58, 6, 100)
-	return (format_context.ctx_flags & AVFMTCTX_UNSEEKABLE) != 0;
+	return (format_context.ctx_flags & AVFMTCTX_UNSEEKABLE) == 0;
 #else
 	(void)format_context;
 	return false;