What program can i downmix 6 ch .ac3 to 2ch .ac3

[atropos]

I need to do this because DVDMaestro seems not to accept the 6ch ripped file.

Thanks,
atropos

[KpeX]

AC3Machine (http://www.doom9.org/ac3machine.htm) will do it using ac3enc - however ac3enc can produce buggy streams and is not recommended for any type of archival purposes. Otherwise look to commercial encoders, use forum rule 1, the answers are out there.