Does anyone use a powerline adapter with a Humax Youview box. I have purchased a netgear and a TP unit and neither of them work with my Humax box. I've been told that a TP TL-PA4020kit will work but I really don't want to shell out yet more money only to find out it doesn't work.
Sorry, not clear what combination you are using/ have tried. Do you mean you used a pair of TP devices (if so, which model) and a pair of Netgear devices (again, which model), or one of each (?!?)... whatever it is you have used, some identifying model numbers and if possible, expected speed (14, 85, 200, 500 Mbps) would help others understand what's not been working OK.
I've used various devices (sometimes just 2, sometimes up to 4) with clients to connect larger homes, and before Wi-Fi was standard with most machines (eg connecting a desktop in an upstairs 'office' to a router on another floor, and have had very few problems - they can run for years, until such time as a really hot spell might lead to overheating - the case is often glued to the area holding the mains plug and transformer, and with very little airflow, so sometimes one can end up pulling the case off the (live!) mains transformer).
Also, have you tried anything other than the Humax (eg ethernet cable from a laptop, and turn laptop Wi-Fi off), to check if the powerline units work, but the Humax is playing up (or perhaps not even playing up - if the Humax was set up with some network settings and they weren't compatible with the router, then the powerline units would not be causing the problem, just network settings)... So have you tried the Humax with a cable direct into the router (if possible - I appreciate this may be awkward... if your Humax is satellite and cannot be moved closer, then it might be a case of a long phone cable and take the router to the Humax to check the two work)