DafOwen

I'm getting some disconnect issues on my K70, but it also affects my mouse. Not sure if it's the keyboard, Windows, drivers or motherboard. But while investigating this I found a bunch of posts suggesting looking at the power options of Windows for USB devices. Might help you. e.g. https://felixwong.com/2015/03/solved-microsoft-wired-keyboard-200-disconnects-and-makes-usb-connection-sound/ It seemed to help me initially - but issues have started again

Ctrl + Alt don't seem to have the same issue - maybe use those instead...?

ALthough the K83 dongle isn't sold by Corsair UK Seems they do sell the one for K63 I wonder if they're the same thing ? https://www.corsair.com/uk/en/Categories/Products/Accessories-%7C-Parts/K63-Wireless-USB-Wireless-Receiver-and-Cable/p/CH-8970047-WW

From a brief check online - seems the keyboard has two connectivity modes : 2.4GHz and Bluetooth. I'm not sure about the 2.4GHz method - but I imagine any enabled computer or Bluetooth dongle should be ok if you can't get the genuine dongle.

Most people clean computer parts with Iso Propanol, or common name (from chemist/pharmacy) = rubbing alcohol. Enough of a solvent to clean stuff - but not too much so that it melts plastic. (e.g. Acetone would melt stuff) If cleaning CPU's you should get 90%+ purity But a keyboard - common rubbing alcohol should be Ok (usually 70-80%)

That happened to my K70 red after a few months - I sent it back for a refund