Metallic noise

It could be that over time some hammers have become grooved and now produce a slightly brighter sound. Hearing it like this, I don't understand much.
But are you referring to the moment of impact or the sustain of the sound? In the second case, it could also depend on the string, perhaps oxidized at some point or no longer perfectly adhering to the bridge (and therefore the tuning must also be checked).
Furthermore, do you notice this in that sector in general or with specific notes?

Thanks for the reply Musiker.

I am referring to what can be heard at second 16. When the string is struck multiple times, a metallic noise can be heard. The phenomenon increases if we have the forte pedal depressed. A technician came over and advised me to put a rug under the piano, my floor is parquet, and he voiced the hammer. The phenomenon can be heard in almost all the strings of the 2nd octave.

I won't put the rug down yet, but if you also think it will solve it, I will go buy it. Thanks again

I believe it is still an intonation problem. In any case, it is right to check the adherence of the strings to the bridge. The felt seems like nonsense to me. Save your money. Naturally, another cause is precisely the hammer grooving which, in addition to making the sound harsher and harder, produces a "dirty sound" as we approach the mid-high range. It is necessary to see the condition of the hammers, redo the tuning, and review the intonation. Also check, during the voicing process, the planarity of the strings in each unison, which must be struck simultaneously by the hammer.

Or even the level of the two strings ...what do you say Paolo? Bye

Thank you all for the answers.

I realize, dear Maestro Ferrarelli, that this instrument needs good and deep maintenance. I believe, in my very modest opinion, that with a skillful adjustment it could give much more both mechanically and sonically.

Can you give me some indication as to whom I could contact? I live in L'Aquila.

Thank you again.

of course Giovanni. Let's say that during the tuning intervention, a serious technician checks the level and the flatness of the strings.