audio did not load in virtualdub

[tatsit]

hi,

i use dgmpgdec149 to demux the audio and mux it back using avisynth with the following script
LoadPlugin("W:\Program Files\AviSynth 2.5\plugins\mpasource.dll")
LoadPlugin("W:\Videos\dgmpgdec149\DGDecode.dll")
video=mpeg2source("W:\Recorded Video\WinTV_05.d2v",ipp=true,cpu=4)
audio=MPASource("W:\Recorded Video\WinTV_05 T01.mp3", normalize = false)
AudioDub(video,audio)

it works perfectly, the audio is there, but when the script becomes

LoadPlugin("W:\Program Files\AviSynth 2.5\plugins\mpasource.dll")
LoadPlugin("W:\Videos\dgmpgdec149\DGDecode.dll")
video=mpeg2source("W:\Recorded Video\WinTV_05.d2v",ipp=true,cpu=4)
audio=MPASource("W:\Recorded Video\WinTV_05 T01.mp3", normalize = false)
AudioDub(video,audio)
Trim(41702,42832)
Decimate(cycle=5,mode=3,quality=3)
ConvertToYUY2()
Cnr2("xxx", 4, 5, 255)
GuavaComb(Mode = "PAL", Recall = 83, MaxVariation = 25, Activation = 40)
PeachSmoother()
VagueDenoiser(threshold=4, method=1, nsteps=6, chromaT=0.8)
temporalcleaner()
LimitedSharpen(ss_x=2.0, ss_y=2.0, Smode=2)
colorYUV(gain_u=15)
tweak(sat=1.2)
Telecide(order=1,post=2,blend=false,vthresh=30,bac k=1)
Crop(8,0,-10,-0)
BicubicResize(640, 480)
ColorYUV(levels="PC->TV")


there audio doesnt load at all. help, this is really frustrating..