Same issue here. Glad to read on this topic. I couldn’t find much online.
That said I stumbled upon this, that says washable sticky lint rollers work wonder to remove the filth on sticky parts:
And cover your push with a cloth after use. Light seems to also have an incidence.
Edit: Washable roller in action : https://www.youtube.com/watch?v=zHgV2g691o8&feature=youtu.be
I always thought the rubberized parts went to shit from dust build up. It’s interestig to learn heat plays a major factor.
I have had great results with cornstarch for my little phatty pitch/mod wheels. It binds to the sticky stuff and it rolls right off the wheels.
Might interest some folks that you may still be able to get upgraded replacements for the LP mod/pitch wheel section that have improved pitch spring and are better weighted ( also a bit more rugged I think). I had the older ones replaced as I sent mine in for CV output mod and stiffer voyager key springs. It was $50 to have both installed, it might be something you can do at home though and possibly cheaper to order without installation…
It depends on what the manufacturer values and which raw material was chosen for the rubber keys. For reasons of cost, natural rubbers are not used for such products. These are probably TPEs (thermoplastic elastomers).
In order to obtain the rubber-like properties, plasticizers must be added to the plastic. Over time, these plasticizers can emerge from the structure of the plastic chains and remain on the surface as an adhesive layer.
TPEs are particularly susceptible to hot water, water vapour, oils, fats, alkalis and alcohol.
In addition, UV stabilizers are added to slow down the glibbing and embrittlement of the keys. As mentioned before, it depends on the quality of the raw materials and additives.
We carry out ageing tests
for our articles and I can say that as a manufacturer of plastic products it is really difficult to guarantee consistent quality over a longer period of time.
We only purchase the raw material with certificate and fill it into the material hopper of the injection moulding machines. But which components the manufacturer of the raw material really mixes with me is difficult for me to understand. We only use simple plastics such as polyamide and know the properties very well.
But with TPEs, the proportion of additives is extremely high and therefore difficult to estimate.
Aw man that’s sad. Sorry to see that.
Dang… That’s weird… 
Ouch…
I’m also concerned that my Lenovo ThinkPad X1 Extreme laptop might be subject to the same issues. It’s got a coating that gives it a mat look and slightly rubbery feeling, similar to my Push 1. Mat look is awesome but a complete fingerprint magnet, and I don’t have especially sweaty or greasy hands at all. Poor design choice, looks over practicality.
My Push 1 doesn’t show any of this, but it’s hardly been used at all and stored in a dark place.
If I were you I’d write to them with details about how you’ve kept it and send them those pics and see if they’ll do something about it warranty or not… If they say no politely ask to speak with someone higher up like a support manger or customer relations or something and ask again…
So I got a reply from Ableton. I think it’s reasonable. They said they’ve had a few reports of this, but invariably it was caused by either a heating device in proximity to the Push, or exposure to direct sunlight. I’m guessing there may have been a couple days when I had my shades open, and sunlight was hitting my unit . Ableton says that because the defect does not affect the functionality, it is not something they can cover under warranty. However, they did offer me the option to pay $118 + taxes and shipping for a refurbished “almost as new” unit. They also offered some ways to remove the finish, which have been discussed here.
I’ll need to think about this for a minute. I think my biggest suggestion to them, aside from not using the TPE coating, is to put a big ass sticker on Push that says Sunlight Will Destroy Product Finish! Keep In Dark Cave At All Times!
Refurb for most companies means that everything externally has been replaced (case and buttons) so I would say $118 is a sweet deal
So… I guess it will happen to the Digitakt and Digitone encoders in the future ?
Silicone (and neoprene as a matter of fact) does NOT like UV. Avoid sun exposure at all costs. Ozone is NOT your friend 
Not so much the encoders in the DT but the coating on the sequencer buttons may show this kind of damage. No one has reported any issues yet though.
Just wait another year or two.
I’d be opting to strip the finish off altogether if I were you, but that’s just me. I always customize and road-proof my gear wherever possible. Hell, if I had to worry about something as simple and ubiquitous as sunlight destroying my instruments, my word… No way. Undress that $hit (wink).
Cheers!
This happened to my XONE 4D! on the jog wheels…took FOREVER , which a ton of rubbing alcohol and scrubbing and picking, to get it clean. its fine now, but man… i cant imagine that happening to a push 2…id LOSE IT…ableton should replace it for sure…thats just not acceptable.
A few thoughts/questions
How long is the offer good for? 1 month, 6months, a year?
Will the refurb purchase come with a full warranty?
Do you have to send in your unit as a trade?
Not sure how long you’ve had the unit but if it has been the better part of a year may be a “new” unit at $118 is not bad at all.
If you can keep your original PUSH 2 and sell its obviously a no brainer and a WIN!
IMHO of course 
Don’t know how long the offer is good for.
Don’t know if the replacement would have a warranty.
I would be required to ship my current unit to them.
I’ve had my Push for at least 3 years. Not exactly sure when I purchased though.
Great questions - I’ll ask about them.
I’m on the fence too because I don’t know what “almost like new” means exactly.
