Key work can become noisy over time due to several factors. The main one is when pads and touch corks/felts get old and hard. Most pads can be replaced easily with a similar product. Occasionally, the need arrises to either change the specification due to a lack of availability, or, to make pads from scratch because the correct thickness pad is not commercially available.
The second reason for noisy key work is down to wear or sometimes, sadly, poor manufacturing. Fortunately all is not lost and most key work can be brought up to standard.
Please get in contact to discuss your key work and I will come up with a solution.
Click HERE to read about my F#/G# Keys for Kung Classica Contrabass recorders
N.B. As all key work is different, standard pricing is difficult to achieve therefore I can only quote on an individual basis.