How to remove SAP from DVD

[winifreid]

I recorded a movie from PBS and recorded the SAP; I then burned it to DVD. SAP is only on the right audio channel. Is there an easy way to replace the right channel with the left, thus removing the SAP? Thank You

[Baldrick]

Demux the movie with PGCDemux.
Fix the audio with an audio tool like goldwave. Convert to ac3 or mp2.
Reauthor the old video with the new audio using Muxman.
Last Use the replace button in VobBlanker to get the movie back into the original DVD, keeping the menus.

(from https://forum.videohelp.com/viewtopic.php?p=1431412#1431412 )

[winifreid]

Thanks
I have never used pgc before. Do I have to rip the dvd first? I tried using it on the disk itself and it gave me the error "Select a PGC with at least one cell"

[winifreid]

Here is what I did after several attempts. I ripped a a single stream with decrypter. For soem reason when I ripped demuxed streams, the ac3 file had 100s of crc errors and ac3 fix did not help. I then extracted the ac3 file using ac3tool (ac3 extraction). I again used ac3tool (ac3to wav) and just converted to wav selecting to write the left channel to both right and left. For some reason, when I used besweet to convert this wav to ac3, it produced a non compliant file. I could not figure out how to get goldwav to convert to ac3. So I used ffmpeg, which did the trick. I then muxed with muxman and burned with Nero. Don't know if another way would work easier or faster.