"buffer underflow" using gui4ffmpeg:?:

[dlflannery]

I use gui4ffmpeg to re-encode 352x480 mpeg2's to 720x480 mpegs with Dolby AC3 audio to maximize compatibility of DVD's on standalone players. My files come from TiVo medium quality recordings which average 2.6 Mbps bitrate. I usually set the re-encoded bitrate to somewhere between 3 to 5 Mbps depending on how much video I'm trying to pack on one DVD.

Today I tried setting the bitrate to 6 Mbps and during the re-encode ffmpeg spit out a number of messages like:
[dvd @ 0FF3A2000] buffer underrun

I assume this has something to do with trying to increase the bitrate from 2.6 to 6.0 but I wonder if someone could give an explanation of the problem?

My understanding is that ANY re-encoding will further degrade the video but that the higher the bitrate, the lower the degradation, realizing that it is impossible to do any better than what is in the original 2.6 Mbps video. But if I am willing to devote the DVD space to use 6 Mbps re-encoding, why does ffmpeg balk?

[Baldrick]

Tried upgrade to latest gui4ffmpeg? it uses an updated ffmpeg.