Our controller cleaning seems to have fucking WORKED!!!
(Lost a case screw though hehe. Internet says it's M2×6mm... not sure if the thread pitch matters?)
so uh, PSA: if you have stick phantom inputs on your PS4 controller, get you these:
- a can of canned "air"
- a can of contact cleaner (we used CRC QD from the hardware store)
- a philips #00 screwdriver
and take it apart like you're going to replace the sticks, pop the stick caps off, and spray "air" and then cleaner into the sticks (aimed at the potentiometers, which are the teal things on the sides, one for each potentiometer) and wiggle 'em around! (We used both. I'm not sure if both were necessary.)
(this may not fix your problem, especially if it's traditional slow drift; ours was not)
(https://www.ifixit.com/Guide/DulaShock+4+CUH-ZCT2+Potentiometer(s)+Replacement/168194, minus the actual opening the potentiometer cases, I tried to do that and failed miserably)