Anemic sounding - 4 keys- later ok!

[sugarplumsss]

I will make effort to describe the event that had me worried ; worried that is, until the next day I turned on t4; voila the strange sound disappeared!

There are four notes around middle C
They are all a half step apart
Bb B C and Db.
In the area where I play the keyboard a great deal.
So I assumed maybe I "wore them out" from playing this 12 year old board so much.
The situation is:
Three sounds across the split point ( as I always have done - nothing different -
R 1 Rock Piano the anemic sound
R 2 electric piano sounded normal
R 3 Strings sounded normal
Left is bass sounded normal
My standard setup for 12 years.

The R1 voice. An Acoustic piano sounded  low in volume and anemic
Like much of the overtones were missing - which made these 4 notes softer than the surrounding notes
I changed acoustic piano sounds to concert piano from the original Rock piano - with no improvement.
Those 4 notes remained anemic compared to the other notes for entire gig .
I had to use more of R 2 to make up for loss of sound on these important notes.
This is the first time in 12 years this has happened
I turned t4 off and on with no change in the condition either .

I assumed repair man to rescue ( this happened this past Saturday )
But yesterday, Sunday, those  4 notes were perfect as before,
as if the weak sounds had never happened!!

I tried other registrations. With no change as well.... The same anemic sound .

Any ideas what this could be about ?

Edit. Excuse my forgetting what happened the day before the above event on Saturday  , on Friday night
The sounds in R1 maybe R2. Not sure ... but I was hearing disconcerting dropping an octave, in an erratic manner.. very unpleasant effect

I would pay the standard price for a technically adept user to help with my t4
Maybe files have something to do with this ?
Thank you

[DerekA]

Pure speculation - some problem with the velocity sensing on those keys?

TBH if it's now working it would be almost impossible to diagnose, unless someone else has had the exact same issue and recognises the symptoms

[EileenL]

It could be the rubber strips under the keys that have worn. This dose happen from time to time.