And don’t ever be tempted to clean your stylus with alcohol - it can dissolve the adhesive that fixes the stylus to the cantilever - don’t ask me how I know 
WC
A while back there seemed to be a fashion emerging for cleaning LPs with PVA adhesive smeared on, left to dry and later peeled off.
I personally never tried that but have a look at this Google search: https://uk.search.yahoo.com/search?fr=mcafee&type=C011GB0D20140712&p=clean+lps+wood+glue
WC
I’ve tried white wood glue. It works. But it’s not a joy to get the glue off if it doesn’t come off in one piece. I still use the trick to clean uneven surfaces that can’t be cleaned any other way, but not for vinyl.
It’s very effective on very dirty vinyl. But I’ve concluded that very dirty vinyl usually isn’t worth the effort.
Pure alcohol doesn’t leave anything. It evaporates completely. That warning probably stems from people confusing vodka with alcohol.
Some specialized contact cleaners leave a lubricating oil. And some contain a water repellant.
There are 2 basic kinds of these sprays: for high current switches and for low signal switches. It’s better to avoid these lubricating contact cleaners for audio electronics. Some switches don’t like it.
Most contact cleaners in a spraying can don’t contain any lubricant and evaporate completely. As they contain organic solvents, they can still damage some parts, like capacitors, coils, or faders. But I’ve never known pure alcohol to damage anything, if used in small quantities. If you need to soak electronics for cleaning, use pure water with a bit of soap and be prepared to change a component once in a while. My take on that is if the component fails because of water, it’s probably on its last legs anyway.
And you need to dry the equipment for days, even weeks afterwards.
The same goes for ultrasonic cleaning. It’s not a miracle and if set to high or at the wrong frequency, it will damage something sometime. It’s very efficient and will even remove paint layers.
There’s one thing I can’t seem to predict/understand. That’s why some aluminium surfaces change color. Aluminium either has an oxide surface, or an anodised (eloxated?) surface. That’s really hard and shouldn’t change color. But it does once in a while. I’ve had a satin grey front plate of a PLC turn pinkish a while back. Probably some reaction to a coating that came from it’s industrial environment. It came from an industrial bakery. Even after washing you could still smell ammonia.
Oh, don’t wash opto electronics. They usually can’t take it. CD players, anything with an optical SP/DIF in or out, lasers. You simply can’t seem to get them to dry and even a tiny drop changes the optics enough to break it.