Unlikely. Contact your dealer — you shouldn’t have to guess whether there is a problem. Have the instrument looked at... sorry you are having this issue.

Thanks for your reply, Bad Mister. This issue caught my attention after I updated the system to 1.31. Is there a way to bring it back to 1.10 I updated it from to see if the issue was present there?

A firmware update would have nothing to do with the B below middle C....please, contact your dealer.

I've had my new cp88 for a week and I've noticed that in the CFX voice the B which is directly under the middle C often sounds louder than the neighboring notes. It's not that louder but I can't help noticing it every time it happens. Other piano voices do not show this behavior and midi monitor in Cubase doesn't reveal anything drastic. When playing vsti's there is no such anomaly, so I reckon midi notes transmitted by the keyboard have proper velocities. Has anyone else experienced any such thing? Could it be that this is how the originally sampled grand piano was voiced or the samples mapped?

I am also experiencing uneven velocity response amongst a few keys on the CP88. In my case, the keys: A2, C#3 and A#3 are relatively "super velocity-sensitive", whereas the C3 key is not as "velocity responsive", needing much more velocity/force to match the other keys. When changing the touch response to either "Soft", "Normal", or "Hard", I am still experiencing the relative differences between these same keys. When I try controlling the CP88 via MIDI through another controller (eg Montage 8), I get a consistent/even velocity response amongst these notes in question. Just wondering if anyone with the CP88 has experienced anything similar...

I've had my new cp88 for a week and I've noticed that in the CFX voice the B which is directly under the middle C often sounds louder than the neighboring notes. It's not that louder but I can't help noticing it every time it happens. Other piano voices do not show this behavior and midi monitor in Cubase doesn't reveal anything drastic. When playing vsti's there is no such anomaly, so I reckon midi notes transmitted by the keyboard have proper velocities. Has anyone else experienced any such thing? Could it be that this is how the originally sampled grand piano was voiced or the samples mapped?

I am also experiencing uneven velocity response amongst a few keys on the CP88. In my case, the keys: A2, C#3 and A#3 are relatively "super velocity-sensitive", whereas the C3 key is not as "velocity responsive", needing much more velocity/force to match the other keys. When changing the touch response to either "Soft", "Normal", or "Hard", I am still experiencing the relative differences between these same keys. When I try controlling the CP88 via MIDI through another controller (eg Montage 8), I get a consistent/even velocity response amongst these notes in question. Just wondering if anyone with the CP88 has experienced anything similar...

Edit : 08 march 2021 - same problem as May 05, 2020. Notes from MI4 to DO5 sound louder than the others.
So same solution, disassembly and reassembly of the CP88. Everything is working fine now...for a year.

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I had the same problem over a year ago.
Some notes (middle of keyboard C4 to C3) and only white keys. It started out very slowly until it became unplayable, the notes having a much louder volume than the others. In terms of velocity up to 20 more than the other notes for an identical force (measurement made with midi software).
My keyboard went to Yahama, dissasembled, cleaned but the technician did not see anything special. With the keyboard working normally, I was happy.
But 5 months later, it started again.
On a tip from a youtube video and for another yamaha keyboard, I took the keyboard apart, removed and replaced the velocity sensors, reassembled the keyboard and it worked wonderfully ....
Up to 8 months later or it starts again. It's very faint, but enough for me to hear it .....
On the video, the guy disassembles and reassembles his keyboard once a year.
This may be what I'll have to do.
That said, on disassembly, we do not see anything special at the level of the sensors. Can a minimal displacement of the sensors because of the shocks of the keys ...
But it's quite boring
I'll give you the address of the video. The disassembly of the keyboard is different but the system of the sensors is exactly the same as on the CP88.
It is a problem with the sensor, because if you change the software or play a midi file, the CP will work fine.

https://www.youtube.com/watch?v=I9VtTrWxGWA&list=WL&index=30

Edit : 28/12/2021 : Same problem. I had to dissablemby the CP8 again ( third time)...This time I changed rubbers on C3 to C5.