Thank you for your question.
I can understand not want the noise when the toilet is refilling with water.
• This is usually caused by the fill valve in your closet tank.
• The has a small flow hole in the valve and it will whistle or squeal as the water flows in the tank. If it is the float ball style, on this brand there may be an adjustment screw that adjusts for water level and flow control.
• If you take the tank cover off and locate the flow screw you might be able to adjust the flow control to make it quieter when it fills.
• If you cannot get it quieter, there are number of brands and models on the market that are almost silent when they fill.
I will give you a picture of one to look for if you decide to change out the valves.
Thank you for using Manage My Life.