I’m having buffering problems and unable to get movies to open after trying several add-ons and following all the fixes I could find. Could it be that my WNDR3400 needs to be replaced. I’ve had it for years now. Ran all the speed tests and memory checks and all the numbers are ok as far as I can see. As it stands my Firetv on my top of the line smart tv and best marantz receiver we got a little over a year ago.