Just to be clear: that 1700/1800 idle is with the bike fully warmed up? Both my former '22 and my current '23 flip-flopped at 14/15 when warmed up, but had a higher idle when started up cold?
By the way:
1) Was your bike in the shop for something else, routine service, etc.? Just curious what prompted you -- or the shop -- to do the software update.
2) My ears aren't very good off the bike (hearing aids) or on (custom-molded ear plugs from my hearing aid office), so maybe that's why I wouldn't hear any strange sounds, if there are any. That said, my C 400 GT has never, to the best of my sensing things, exhibited any hop on acceleration. I usually give it a fair amount of gas when taking off, by the way. So I'm a little curious about that aspect, too (but glad it's fixed for you now).