Re: applying "audio waveform" effect to group of paths from AI

This is a small hassle to setup, but it works, and you can make an Animation Preset for quick results in the future.

To the layer with all the masks, I tested 6 masks, add the effect: Audio Waveform, set it to mask 1. Select the effect in the Effects Palette, and Ctrl D duplicates the effect (another instance of Audio Waveform). Set the mask to Mask 2 for this one, and be sure to check the Composite On Original box. Now dup the effect again as many times as you have masks, and manually set the masks to 3, 4, 5, etc (and they'll all have Composite on Original checked).

You can select all the instances of Audio waveform and Animation>Save Animation Preset, name it... then in the future you can apply that to a layer with that many masks or less and you'll have what you want.