The 7.1 mix is actually an upscale of the 5.1 mix from the original DVD release and as a result still features most of the new sound FX added back in 2000. Some original sound FX were restored but not much. The only ones Ive noticed were the original whale cry, Brody pumping the rifle before climbing the mast, and the ricochet when the bullet hits the airtank. Many fans were quite pleased the latter was restored and rightly so but personally I dont think it meshes well with the newer sound effects. There were some things about the 7.1 mix that I think improved over the 5.1. Brody’s ‘bigger boat’ line is somewhat louder and not as drowned out by the music as it was on the 5.1. When he says ‘Smile you son of bi***’ its also somewhat louder than on the 5.1 although ‘bi***’ is still obscured by the bullet shot. You can only properly hear that word in the mono mix. Just the same I prefer the mono mix either way although it is a shame that even the version of that track thats in use now has issues.