Gregatron is right - I'm listening to the V3 right now with my Sony MDR-EX57LP earbuds, and both the 35mm stereo and 1993 mixes on that disc have the deactivation sound, but it's so quiet that it might as well not be there. It was actually a bit easier for me to make it out in the 35mm mix than in the '93.

Previously, I also spotted the "and" in Threepio's "and...do take good care of yourself" in both the 35mm stereo mix and the '93 mix. Like the saber deactivation, it's just very faint (but not as faint as the saber to my ears).

I just listened to morgands' 70mm in-theater recording again, and both of them are pretty audible there. Gregatron's theory as to why the saber deactivation is so quiet makes some sense, and as for Threepio's "and," perhaps the mixers put it in at a lower volume to make it seem like was saying it softly and timidly.

In both cases, I'm not sure what's up with the very faint versions in the post-70mm mixes...