Sub making god awful noise on some frequencies

[Irocthestreetz]

I rebuilt my hdc315 ( my first recone) about 3 weeks ago and it was slapping wonderfully well I needed to tune my sq2200.2 so I got at this with my dmm and as soon as I finished up with that this horrible noise started 
https://youtu.be/xUeTAOaA4H8
And another 
https://youtu.be/O87ibnm9md0
I tried a different amp and then finally took the sub out and tried a different sub and got no funny noise from that one so it is without a doubt a issue with the sub. There are no loose tinsel leads or wires or anything else that sticks out. The noise seems to be coming from the dust cap but maybe it's just amplifying the sound? Is there a way to safely pop the dust cap off and check? When I push down on the cap there is no rubbing or scrapping sounds so that can't be coil rub right? Any other possible ideas i can try out? It's mysterious that it started after tuning my amp but ive done it that same way tons of time. And if I didn't shim the coil right It wouldn't had been fine those first weeks would have it? Any help is appreciated thank you.

[deathcards]

i have never reconed a sub before but guessing former may have let go or maybe check the magnets to make sure they didn't shift i can't tell in the videos

might help to post the glue you used

just trying to help those that know

[Irocthestreetz]

The former? And I used the cyberbond ca glue and accelerator that soundqubed suggests. And a whole damn lot of it too

[ShadeTreeMechanic]

Check that the dust cap didn't come loose. Also check that it didn't come apart where the spider meets the voice coil or where the cone meets the voice coil. Hopefully nothing got in the motor gap when you cleaned it up. Also push around on the spider to make sure it's not torn.

[MADVIBES]

check to see that the spider didnt come unglued from the landing. use your phone and download a signal generator and find exactly what freq is is and play that. looking closely at the sub woofer. see if you can play it out of the boz to see if the sound is coming from the rear or front. also look closely to see if anything had come wedged between the cone and spider like a chunk of sawdust or a screw. sounds strange but I have encountered it all.

[Knocker]

My Mayhem 18 was making that sound because one side of the pool of glue where the cone attaches to the voice coil (triple joint?) shattered. On certain higher notes the voice coil would start rubbing on the motor because the whole assembly would kinda tilt because one side was no longer held in place (I think). Not sure what your issue is but that was my experience. Gonna have to recone mine. Hope it works out for you.