Suddenly my captured MPEG files have lost audio when playing in Windows Media Player. There have been no changes to the system in months. I also have Nero ShowTime and Power DVD, both of which play the MPEG files perfectly. I can demux the files, in which case the audio portion plays perfectly in Media Player, but if I re-mux, the problem re-appears. Media Player shows the files as using NVIDIA audio codec. Other media files (other mpg, wav, mp3, asf, wmv) do not exhibit this problem.

P4/3.0, 1Gig RAM, Intel 865 Main Board, audio/video on board, Plextor PX-M402