In high dielectric type ceramic capacitors, a dielectric has a slight distortion when the voltage is applied to it. This causes the physical vibration of ceramic capacitors when the volage at audio frequencies is applied to them. The vibration is tranmitted to the board and amplified resulting in a sound from ceramic capacitors.
The magnitude of the sound depends on not only the material of a dielectric but also the figure
of the capacitor, the size of the board and the mounting state of components. Therefore, you need
to take steps from both board layout and parts selection. Please
ask our company in detail.
For this type of application, we are preparing Low Distortion High Value Multilayer Ceramic Capacitors(CF_LD), Multilayer Ceramic Capacitors with Metallic Frames, LW Reversal Decoupling Capacitors (LWDCTM) and like that. Please try to use them.