Could you try this render type, please? Change the compression "vp9_1280x720_24or25or30fps.webm" to your format size (1920x1080?) /* ************************** */ Render_WEBM: - Filename: yourfile_render.webm - File Format: FFMPEG - webm - Audio: - Preset: webm.webm - Bitrate: 128000 (128k) - Quality: -1 - Samples: fltp - Video: - Compression: vp9_1280x720_24or25or30fps.webm - Bitrate: 0 - Quality: -1 - Pixels: yuv420p - Video Options ( * means changed by me): # 20171119-2100 # based on https://developers.google.com/media/vp9/settings/vod/ # for explanations reference the Cinelerra Manual # 1280x720 (24, 25 or 30 frames per second) b=1024k minrate=512k maxrate=1485k tile-columns=2 g=120 (*) threads=8 quality=good crf=32 speed=4 color_primaries=bt709 (*) color_range=jpeg (*) color_trc=bt709 (*) colorspace=bt709 (*) /* ************************** */