On mine someone had installed a screen lighting kit, and Spektrum sent it back saying that because of the aftermarket parts they would not work on it. However, they didn't charge me the postage on the return. Then I found out how to clean the pot myself like H5606 did and it was so easy I wondered why Spektrum didn't just do it. Some risk management lawyer, I imagine. I'm not complaining since they were nice about the postage, but it seems a bit picky since this is a well-known problem with their product.
Jim