Mpeg2 bitrate question

[befranky]

My goal is to produce MPEG2 CBR stream at the max btr (respect the svcd standard). I've used tmpgenc in CBR mode with video(2590Kbs)+audio(128Kbs). The mpeg produced plays fine in my samsung 611, but at the start of the track there are some freeze (due to the high Bitrate). So I've tried to inspect the mpeg file with bitrate viewer tool. In fact, while the program load the mpeg , it shows an average bitrate that is bigger in the first part of the file.
I've done an other small test. I've cut the same file (with tmpgenc) in more parts and then I've checked them with bitrate viewer. Obviously I expected the bitrate was bigger for the first chunk of the video. Instead all the chunks have a similar average bitrate and moreover, all have the same behaviour of the full video : average bitrate bigger in the first part of the chunk.
Where is the mistake ?
Then I've tried the same Tmpgenc setting with other mpeg files but all of them play a little bit freezed at the start. The easy solution is to decrease the bitrate, but I would like to understand why Tmpgenc produce a variable bitrate (and always at the first 5 seconds of the stream !!!!)

Thanks for any answer.

[Braindrain]

Maybe you should e-mail the author of TMPG. I encode at 2500k, CBR, with no problems. But... I'm using a Pioneer DV-343.