Check the following points.
If you also hear the sound through headphones:
Some piano tones that have a brilliant, clear sound are designed to have stronger high-end harmonics, and for this reason may seem to have a metallic ring. These tones are intentionally designed to faithfully reproduce the original characteristics of a piano. This is not a malfunction. If you don’t prefer this kind of sound, try adjusting how the tones ring out (the reverb and so on) or the string resonance.
If you don’t hear the sound through headphones:
The sound you hear might be a result of resonance occurring within this instrument, among other causes. Please contact your dealer or a Roland customer service center.