It worked great! :) I then tried it with a higher vbitrate of 7000 and vrc_maxrate of 8000 and lower vrc_minrate of 3000. That also worked just fine! :) NO bufferunderflows! Max Bitrate respected!, Picture looks spot on! I think I was pretty lucky to have finally got the right combination of switches that work correctly with the rate control and also allows me to change the bitrate around without reverting back to underflows and spikes. Now the excellent AvstoYuv allows me to input via avisynth I'm very happy. I don't know if Peter Cheats' rate-control and this support for avisynth could be worked in to Mencoder, it's very good and has really helped me. There are surely other people who would like it. Now I'm setting up the full clip which will probably take a day and a half I estimate. Since I have visited Doom9 wanting to encode to Mpeg2 for DVD I have ended up with three solutions to pick from- very nice, I'm very happy and appreciative :) :cool: :eek: EDIT: I thought I should make it clearer, that Muxman (by MPUCoder)v0.11b accepts and processes the M2V and reports no underflows. This is how I tested to check if DVD compliant mpeg2