Hearing a buzzing sound from your digital piano when you accent the 3rd octave C can indicate a potential issue with the instrument. While it's difficult to diagnose the exact cause without further information or inspection, here are a few common possibilities:
Speaker vibration: In some cases, the buzzing sound may be caused by the vibration of the piano's internal speakers when certain notes or frequencies are played at higher volumes. This issue can often be resolved by adjusting the position of the piano or tightening any loose screws or components.
Loose internal components: Vibrations from playing specific notes may cause loose components within the piano to vibrate and produce a buzzing sound. This could include loose screws, connectors, or other internal parts. Inspecting and tightening any loose components might alleviate the issue.
Damaged or worn-out parts: Over time, certain parts of a digital piano, such as the keys or the internal mechanisms, can become worn or damaged. If the buzzing sound is localized to a specific key, there might be an issue with that particular key's mechanism or its contact with the sensors.
If you are experiencing this buzzing sound consistently and it is noticeable and disruptive, it would be advisable to have a qualified technician inspect your digital piano. They will be able to assess the situation more accurately, diagnose the specific cause, and recommend appropriate repairs or adjustments.
Remember, it's generally better to address any issues or concerns with your musical instrument sooner rather than later to prevent further damage or potential performance problems.