What do you think causes the crackle and clicks we hear?

Johnss, I have looked at many new records under a binocular microscope and have seen no such residue. The occasional finger print, some dust but no calcium carbonate. You see these round crystals in horse urine. I look for calcium pyruvate crystals in human joint fluid all the time differentiating pseudo gout from gout ( uric acid crystal arthropathy)
Uric acid crystals being negatively birefringent needles versus thepositively birefringent rhomboids of calcium pyruvate. 
The mold release agent is a very small part of the PVC additive mix. Additives such as plasticizer, the mold release agent, carbon black and some other stuff make up 2.5% of record PVC mix. It is in the mix. Not on the surface. 
Contrary to popular mythology generated by the record cleaning industry new records do not require any special cleaning as long as static is neutralized and incidental dust is swept out of the way. Only poorly kept used records require cleaning. I personally do not buy used records. I can certainly understand using a record cleaning machine on them though. But instead of all that record cleaning stuff I would rather spend the money on new records. My perspective may be different as I have been collecting records for over 50 years and have a fine stash of vintage records. 
 

MC you really need to go digital. This stuff is getting to your head or whatever you call it:)

Good one. Its just hard sometimes to take this stuff seriously. I mean it is after all records we’re talking about.

Its like the guys on Rennlist asking why do my brakes squeal? Why can’t Porsche make a car the brakes don’t squeal? VW can. Mercedes can. Why not Porsche? What is so hard?

And there’s really only two ways to go. One is a deep dive into brake compounds, calipers, temperature ranges, kinetic energy, on and on. The other is dude, its a Porsche. If you absolutely can’t deal with it go ahead, drive the Beetle.

Its static electricity, dirt, dust, wear- all those and more. If you absolutely can’t deal with it, there’s always the Beetle.

I can’t answer the why. I don’t know what causes the clicks and pops. I do know that a good cleaning helps. I use an RCM and I do a rinse and vac after using a cleaner. I use pure distilled water to rinse even though I’ve been told the water molecules are too big to get in the grooves. All I know is it works. And I will do just a water rinse if there is a lot of static on a record. The moisture kills the static. A Zerostat works well for me if the static isn’t terrible. I’ve noticed some of them work better than others. I think there quality control was never great. And there is a proper way to use it that I see most people get wrong. Youtube has plenty of examples of how to do it right. I still have some LPs with noise I can’t get rid of. I either live with it or I find a better copy. 

@mijostyn

If I could post photos I would, I have over 300 JPG files of groove images and all show carbonate in the bottom of the groove. so not sure what grooves you have looked at.
All I am doing is trying to remove some of the mystery behind LP cleaning and show more that getting clean LPs requires a bit of work if you are using VAC or US type cleaners, and can be done.
Have not tried the sink wash type cleaners so can't offer any insight on them.

If anyone wants to do a simple test, its quite easy. can be done on a vac machine (VPI or NG). use your favorite cleaning solution, apply it to LP. spread evenly across the LP surface.  Let is sit for 10-15 min then vacuum off.
Go play the LP. you will notice a much quieter background.


  

use your favorite cleaning solution, apply it to LP. spread evenly across the LP surface. Let is sit for 10-15 min then vacuum off.

@johnss   That sounds simple enough, I'll give a try shot.