X1C 1st generation - Volume buttons stuck?

[agricola]

Hi all

This question is about the +/- volume buttons above the keyboard (in the bezel). The - button makes a 'click' sound when I press it, but the '+' button does not. Both buttons work.

It this normal for this model, or should the touch&feel of the two buttons be identical? The computer is still under warranty so I might be able to get it repaired.

Thanks

agricola