Dispensers should have random sounds

Activating several dispensers or droppers at once will create an excessively loud clicking sound. This is because they all play the same click sound effect at the same time, causing the sounds to overlap exactly and multiplying the loudness by the number of dispensers. This also occurs when several dispensers that fire projectiles (arrows, potions) are activated; in this case the bow firing sound is played.

In contrast, pistons, despite having only a single sound effect for opening and closing, play them at randomized pitches, causing the sounds of activating multiple pistons to not overlap perfectly and therefore making the volume much lower.

In my opinion, dispensers should either play the clicking sound at slightly different pitches, or they should get several distinct sound effects (like most other sound sources) to add some variety.

This video demonstrates how the sound of activating multiple dispensers is overpowering compared to activating a single dispenser, several pistons or several iron doors.