muxing is slow in vdubmod

[galocza]

hi,
ive searched the forum but havent found an answer:
when i try to mux an (xvid) video and (vbr mp3) audio in vdubmod, the process gets much slower than im used to. in nandub its ok. 22min video, vdm: around 250fps, 2:10, nandub: around 3200fps, 0:10.
maybe i did something in preferences though i really cant guess what could be related with this issue (and i dont touch what i dont understand).
i had this problem before and used nandub for muxing, but i really cant understand this problem and id like to fix it.
thx,
galocza

[stephanV]

muxing speed also has to do with e.g. file properties (e.g. frame size), did you compare muxing with the same files? and if nandub is faster, why not use that?

[galocza]

of course the very same files.
and yes, i could use nandub for that but
1 im interested what the problem is
2 i hate to use 2 progs when the same can be achieved with one
3 vdubmod worked at the same speed but reinstalled my system so i guess i set sg wrong. i just hope that somebody came across the same problem and knows about a solution.
thx anyway,
g