diff --git a/src/video.cpp b/src/video.cpp
index e847b629..30dda46d 100644
--- a/src/video.cpp
+++ b/src/video.cpp
@@ -978,9 +978,9 @@ std::optional<session_t> make_session(const encoder_t &encoder, const config_t &
   }
 
   if(video_format[encoder_t::CBR]) {
-    auto bitrate        = config.bitrate * (hardware ? 1000 : 800); // software bitrate overshoots by ~20%
+    auto bitrate        = config.bitrate * 1000;
     ctx->rc_max_rate    = bitrate;
-    ctx->rc_buffer_size = bitrate / 10;
+    ctx->rc_buffer_size = bitrate / ((config.framerate * 10) / 15);
     ctx->bit_rate       = bitrate;
     ctx->rc_min_rate    = bitrate;
   }