What you might be hearing is the way it is supposed to sound.
If your previous damper had bits of rubber coming out if it… that rubber is what the outer ring weight of the damper floats upon… and if your previous one was so soft and degraded that it was coming apart… you may have become accustomed to how it was NOT supposed to sound and behave.
Everything seemed smooth to me the steering wheel was not vibrating at all and it seemed like no secondary vibes were being transmitted through the vehicle but only you can tell us that for sure…
Now that the main pulley is new and the rubber damper is also new… you just may be hearing your auto tensioner on the serp belt moving around as it was designed to do ( the hollow sound i mentioned)
With the old degraded damper it would put less strain on the tensioner bec the damper was so soft…and now with a new damper the auto tensioner moves a great deal… as its designed to do.
Unless you are feeling vibrations in the wheel or your pedals etc… you are in good shape.
Also… with the engine running open your hood and watch your serp belt and look at the main pulley… if the main pulley is wobbling that is a problem… if it looks like it is standing still while its actually spinning at 800-1000 rpm’s then it is running “true” and there would be nothing to worry about at that point. Rev the engine while you are looking at the main pulley… or have an assistant rev the engine a bit for you. Take a look and report or post that video
That main pulley should look like its standing still while its spinning… no wobbles is what you want…and if that is what you have, you and the engine are in fine shape.