Here in the UK I have not seen any reports of buttons not working properly. I run my own forum here and have not had one post saying that members are having trouble with buttons at all.
Well Eileen this thread has been running almost 2 months, and I made 2 observational comments about this issue in posts in October, though the posts were not specific to this issue. In fact like others I thought it was down to user error. Quite a few of us ARE in the UK, and Herefordshire where I live was still in the UK the last time I checked.
I'm on my second 970, and sadly this one does the same but nowhere as frequent as the first board, I tend to set up lots of banks of registrations like many others, with all my favourite voice mixes etc.etc. So once set I don't need to use the A-E and F-J keys too frequently. It becomes noticeable when you are using it a lot, which sometimes we have to. Often I can press buttons as many as a dozen times or more and it's fine, then it will either not record the press and I need to press it a second time, or the most annoying issue where it detects 2 presses, when I've only pressed it once, and it returns back to the main screen, so it means you have to press a button again to get back to the voice selection screen as clearly explained in this thread many times.
I'm pleased that your 970 works 100% perfectly Eileen, and TBH I thought this second one did too when I received it, but while going through the voices a few days later it became apparent it too suffered the same issue albeit to a lesser extent.
I'm 99% certain its caused by a batch of flaky button switch panels, so we will have to see what Yamaha do about it.
It's NOT a catastrophic fault, and many users will likely not bother, thinking it's the way they press the buttons, but there's no doubt it can be annoying if one spends some time trying different voice combinations which of course we do occasionally.
So just because some do not have the problem does not mean it does not exist, because it certainly does. In fact recently while shopping in Worcester with my wife, I popped into a music dealer there to check out a couple of pianos, he has both the 770 and 970 models on display now, and on checking the 970 they had, I found it too exhibited the same issue when pressing those control buttons, and when I pointed it out to the sales guy, he said...do you know I've never noticed that before I thought it was the way I pressed the button, he just shrugged it off as no big deal, though he did comment that he thought the buttons didn't feel good.
Why Yamaha says no-one's reported it is utter rubbish, as I've emailed them twice and spoken to them, my own dealer also said they would have a word with them about it, as they would have returned my 1st board to Yamaha UK for repair, plus don't forget the OP who started this thread said Yamaha had changed his twice for the problem, so they obviously know. Maybe they are not sharing information between themselves, I know Yamaha UK were not happy the OP started this thread which I suppose is understandable.
Hopefully, Yamaha will find a solution, but I can assure you and Yamaha, there are boards out there that do have this flaky control buttons issue. I might be old, but I'm not ready for the loony bin yet...lol I've been pressing keyboard buttons for more years than I care to remember and none have ever given me a problem before, the other 4 boards I have here all work great. AIS lets hope Yamaha finds a solution/fix.
Best wishes... Cameron