Now to clean the potentiometer. Some people suggest dismantaling the potentiometer itself to clean and using contact cleaner. I didn't do this. Instead I sprayed isopropyl alcohol into the small window towards the bottom of the pot (indicated by the arrow).

Turn the pole from side-to-side around 20 times each side. I did this a couple of times to try to remove any gunk and dirt spraying more ispropyl alcohol as required.

After ensuring the pot was dry I added a little bit of singer oil for some lubrication. I'm not sure this is the best thing to use so you may need to do some additional research.

I'm not an expert on cleaning potentiometers (this was my first time), so please do some research and follow the best advice.

The potentiometer in my unit seems to be a Fanrui RK166N single and vertical F shaft (rated at 50,000 rotations). Link to possible part: http://www.dgfanrui.com/en/rk166n-%E5%8D...