Popping sound from speaker at high level

Hello, a pair of infinity kappa-5 speakers I own, make a loud popping sound when played in high levels, especially if there is a lot of bass. At first I thought it was the amp, but I've tested it with a number of amps and this was repeated with all of them. I am hardly putting 20-30 watts in them when this happens, it doesn't sound like clipping or distortion and the cone movement looks fine. The popping is not happening on a specific interval, they sound sporadic. Could this be failing capacitors in the xover ? The speaker wire connections are all secure.
 
Voice Coil hitting the backplate attached to the magnet
I don't think that they do that. How can I check. I am not sure how this would sound. I am hearing a pop like a small firecracker. In their spec sheet they state that they can handle 20-100 watts ( rms, or peak i dont really know), but I am definitely not overpowering them. They also don't sound bad so I wouldn't think they have deteriorated to this point (woofers have been refoamed )
 
Well, I opened them up. The crossover looks fine and measures fine. It's quite a complex one for a 2way system. It has a high pass for the woofer, a potentiometer for the Tweeter level and even a tvs diode.
The caps look new so they where indeed replaced by the service company, I don't recognize the brand though and they are electrolytic but I mean film caps would surpass the cost of the speaker itself.
I will attach a couple of pictures in case someone is interested,though I didn't disassemble it further because I could measure the caps.

The speakers have been refoamed after the original surround had been completely destroyed, so expect if the service company did a big mistake that shouldn't be a problem. At least that's what I can see.

I don't have an oscilloscope so I cant prob the pops.
This leaves the spider, as the only suspect which looked normal..
Could it be the tvs diodes?
 

Attachments

  • IMG_20220913_162905.jpg
    IMG_20220913_162905.jpg
    417.5 KB · Views: 64
  • IMG_20220913_162914.jpg
    IMG_20220913_162914.jpg
    427.6 KB · Views: 48
  • IMG_20220913_162926.jpg
    IMG_20220913_162926.jpg
    371.7 KB · Views: 51
  • IMG_20220913_162946.jpg
    IMG_20220913_162946.jpg
    399.6 KB · Views: 58
  • Screenshot_20220913-172039.jpg
    Screenshot_20220913-172039.jpg
    161.1 KB · Views: 4,000