Hyundai Repair: cruise control/trans down-shift, throttle application, dealer stock

Question
2010 Sonata 4cyl.  With cruise set @60-65MPH transmission will down-shift at slightest rise in roadway.  If drive car in same siruation w/o cruise or w/cruise but shift lever moved to 5th gear, problem goes away.  Possible speed sensor?

Answer
Hi, Walt.  This sounds like a normal condition.  The cruise is limited in how much it will apply the throttle.  If it isn't able to get the degree of speed increase it desires (in a predetermined time period) with that throttle application, it will request the transmission to downshift one gear.

I do see that there are two programming updates for the engine and transmission control modules on the 2010 2.4L Sonata, and depending on your car's date of production, one or both may apply.  The first was a campaign on dealer stock units with no description in the technical service bulletin about the effects of the update.  The second was to improve acceleration feel from a stop and improve shift feel.