Here's Albini recounting buying child pornography while in Hamburg:

Jaded as I am, I can't help but flip seeing a girl and guy of twelve or thirteen, tops, ramming Martel bottles up each other's asses. These are not the Dutch equivalent of abused trailer-park kids, either. They look to be in excellent health and seem to be honestly enjoying this. Makes all the conventional arguments against this kind of thing seem really silly.

They're kids. Kids like to play with their own and other people's privates. They're just being photographed at it. Now, people who get a voyeuristic charge out of watching them, like me, I guess, well, we've got some grip-on-reality problems. There's maybe 1% of all pornography that has any effect on me, and it's definitely not a turn-on very often. But when it is, and it's as weird as this, it's pretty hard to take.

And here's him promoting his friend, Peter Sotos', chld pronography magazine:

The cover of PURE 2 is a guy holding open a toddler's puny hole so his spuzz can dribble out. The girl is past crying. She is destroyed. [...] Like I said, I like that sort of thing

Sotos later defended his use of child pornography in cout, stating "child abuse is a sublime pleasure"

https://www.chicagotribune.com/1985/12/06/100000-bond-in-child-pornography-case/

Albini also produced an album for Sotos called Buyer's Market, which Wikipedia describes as "sound collages of spoken word samples from parents, law-enforcement officers and victims of s*x crimes and pedophilia". When asked about his relationship with Sotos in a reddit AMA, this is what he had to say:

Peter's an old friend. I've known him for 30 years or so. I'll help him do whatever he wants to do, from wash his car to edit his album.