2adicoto>
AFAIK these TV series are mostly coded as VCD video MPEG-1 stream and the 48.000 audio would be not correct for VCD standard, reasonable software will force 44.100 when selecting VCD profile.
I think that the decoder is not the case of audio unsync, IMO it is due to primary bad grabbing with all arising consequences. On a hardware wihout professional synchronized A/D converters I would recommend allways to grab at 48.000 and then to resample to 44100, the time difference after cca 1 hr (the usual length of an episode) will probably stay as low as no further time stretching will be necessary.