This is our standard reply on adhesive removal.
For starters, we recommend you watch our instructional video on how to change LCD earpads
here.
You don't need to remove all the old adhesive for the new PSA rings to work, but you'll need to remove any base layers from the old earpads before the adhesive will stick. There are a few ways to do this, depending on your comfort with the various tools, how old the previous adhesive is, etc. Use caution and work within your comfort zone to prevent any damage and/or injury, which Audeze cannot be held responsible for. The methods below are for guidance only, and any actions taken are done so at your own risk.
Before you begin removal of the old adhesive, be sure to cover the opening to the diaphragm with a bit of paper and some low-tack tape to prevent any damage to the diaphragm itself.
Here are three methods we've found to work in most cases, from simplest to most effective:
1. If you apply some masking tape to the old earpad material, then burnish it firmly using a small tool like a tongue depressor, popsicle stick, etc, the tape will sometimes peel the old material off when removed. Be careful not to adhere the tape to the wood rings or any other delicately finished surface.
2. Remaining layers can often be scraped off with a slim non-magnetic implement. WARNING: Using metal near the drivers can easily cause damage to them which would not be covered by warranty since they may be attracted to the very powerful magnets.
3. If you're comfortable with naphtha (AKA mineral spirits, paint thinner or lighter fluid), you can dab a small amount on the old adhesive with a cotton swab that's been dipped in naphtha and let it soak in for a few minutes. You want to moisten it enough so the naphtha can dissolve the adhesive, but not so much that it runs off to damage other parts. Once the naphtha has been in contact for a little while, you can often peel the residue off, then wipe clean with a dry cloth. Let the naphtha evaporate completely before installing the new earpads. WARNING: Naphtha is highly flammable and fairly toxic, so be careful not to breathe the fumes or work near any sources of ignition. Use in a well-ventilated area and follow the warnings on the label.
If you're not comfortable at any point, please stop and let us know so we can assist before any damage or injury occurs.
. I have a 2021 from the B stock sale, but your tips about putting it on slowly plus the Valsalva maneuver really helped, and I think my ears have adapted. 
