Mux rate too low for data rate?

[SiCN]

So far I used bbMPEG for muxing without a problem, but there is always a little Note in the status window of bbMPEG saying "NOTE: Mux rate may be too low for data rate?", does one of you know what that means and how I fix it. I mean, the SVCDs work fine anyway, but who knows... maybe not always.

[RemoteCtrl]

This message is shown when the peak bitrate for video+audio is higher than what is allowed by SVCD spec. Fortunately there are buffers flattening the peaks over a short period of time, so you should worry only if you actually get buffer errors during multiplexing.

[adam]

And if you do get buffer errors than you can set the forced mux rate to 0 which makes bbmpeg select the appropriate number for you.