Why Does My Sony Tv Volume Only Go Up And Down In Increments Of 25?

[numan]

Ever since my 8 year old Sony Bravia KDL series TV was sent in for repair a couple of years ago, the volume only goes up and down in increments of 25 from 0 up to 100! I have a Sony DVD player too and, as that remote also works with the TV, this does the same thing and consequently effects sounds in the same way when watching a DVD. Going by this, I'm guessing it's the TV and not the remotes. I've spent hours of searching forums and just general searches, but to no avail. Even the repair guys couldn't help me. It's now become a mission to solve this problem, so any help would be more than gratefully received..

[numan]

Can no-one help me? :(