[HTC One S] Sneakyghost:
Some more thoughts from me too. Nothing well researched. Sorry. Was intending to do a bit more learning on the buttons actually but had no time.

Considering that even HTC is already believing in the Radio Interference Theory i tend to stick with that.

The only thing i could still hold possible is the flexing/lose antenna as that would make the phone significantly increase emissions and that again could trigger the buttons playing up, although i had a close look at it and when i use force on the bottom back cover (which apparently holds the mobile signal antenna) while there is transmissions going on there is no reaction.

When switching the screen on, there usually is a lot of synchronizing and checking going on, thus more radio, so that would be possible.

When in pocketses (it is our precious.... we will keep it close in our pocketses...) it tends to warm up a little and maybe flex too. Both higher temperature and bending might make the antenna lose contact and increase emission strength. So not quite impossible either as a reason.

I had the very worst misbehavior yesterday while driving constantly at around 100km/h for 30 minutes, doing cell hopping. That makes the phone desperately trying to keep any and all connections alive. I was driving through low Edge coverage areas mainly. My wife was holding the phone and she could basically not use it for the whole drive. When we stopped the car the random behavior began to better up immediately.

One last thing: the observation that this issue disappears after a hard reset is nothing special. It will come back eventually. I have done about three or so factory resets and new installs and it was always normal after that for 24-72 hours. Only after some time the issue would come back.

Also there seems to be longer periods of time where there is nothing extraordinary happening without doing a hard reset. For this reason, i think the seemingly rational theory that it betters after a Factory Reset is most likely just coincidental. I bet there will soon be someone coming in here saying "Oh well, my device did it right after i Factory Reset it"...

---------- Post added at 04:34 PM ---------- Previous post was at 04:25 PM ----------

I don't think so, at least not ONLY a software problem. Rebooting makes the phone cut off all radio emissions and when coming back online it rebuilds the connections. All components of the phone are electrically reset and thus interference would have to build up again first. So after a reboot it will most likely be OK for a while.

After all, we have to take into account that the currents flowing on the boards in the phone are very low and probably quite susceptible to radio induced noise.

I have once read a theory that one day it might be impossible to make Computer mainboards even smaller because the electricity would have to become weaker and weaker too and at some point the pure atmospheric radio noise would cause so many malfunctions in the circuitry that we simply couldn't use the boards anymore. So i find this whole radio interference thing very very interesting and i would even be disappointed if at the end it turned out not to be true at all :D