Okay hivemind, what do you think would be the auditory equivalent of "undulating"?
Are you looking for musical terms like vibrato and tremolo?
Although "vibratoing" or "tremoloing" don't sound like words, do they? But they do produce many google results....
sussurating?
That's what sprang to mind for me.
Man, car insurance is so weird. Now that I actually have to get more than just liability coverage, I've checked the rates of most of the top companies, and Geico is by far the cheapest. It beats Progressive and Allstate by $100 and Esurance and 21st Century by $300. For the same coverage! It's so bizarre.
Undulating can apply to sound. Rolling? Rhythmical? Tintinnabulating?
Of the bells, bells, bells!
Undulating can apply to sound.
Yeah? Because that was my first impulse, but I've stared at this damned sentence for so long, I wasn't sure any more.
I think that you also might want to consider your audience when you select your word. I have great love for precision in word choice, but the perfect wprd isn't perfect if your audience doesn't get. Of course, perhaps this is coming to mind because I'd never heard "susserating" before. OTOH, I learned a new word!
I'd be inclined to drop muffled and let crash stand. (Also would note that the sentence isn't complete, which I'm sure you're aware of.)