Strange Grimy Residue Inside My Receiver and Electronics

[Nitruc]

We clean/vacuum our studio apartment here in Los Angeles almost weekly. I don't always run my AC so it can get a little hot in the apartment, but we usually keep a oscillating tower fan running and/or use the AC. We also have a humidifier which might be adding to the problem.

Being in LA everywhere you go has a little bit of smoggy dust that settles shortly over time if you ever keep a window open... but we're also getting a strange grime residue on the outside and insides of electronic equipment as you can see in the picture below. I'm worried that this could lead to issues with the electronics and much shorter lifespans... Is this just due to the room being too hot and having too much moisture? Or could it be related to the carpet or wall paint? How can this be checked or prevented?

In the picture below you can see my receiver with the top removed and how the side panel is getting this grime. The biggest circle shows grime on a clear plastic strip while if you look a little to the right above that you can see another clear plastic strip with barely any grime on it.

 

[hang-the-9]

I don't see the picture at work, but do you smoke? If yes, that may be it. I have seen computers come from houses with smokers and thay are coated with what is almost a stiky film that ofcourse collects dust like tape.

 

[Nitruc]

I don't see the picture at work, but do you smoke? If yes, that may be it. I have seen computers come from houses with smokers and thay are coated with what is almost a stiky film that ofcourse collects dust like tape.

Nope. No smoking or anything else burning besides cooking sometimes with the vents on and window open. Why I'm also a bit concerned about my health too considering this is something you would see in poor living conditions, not an apartment that's being cleaned weekly.