I have the same thing ,PFO de with 400watters. I to have had issues with the sockets. I got new sockets from Custom Aquatic. The new sockets were a little labor intensive to install due to the salt corrosion. I basically ended up rebuilding the pendant. It is alot easier for me now as I put new screws in as well (stainless)I am not familiar with the luminarc,but they might have the same type socket and same troubles? Well I just looked at Custom Aquatics site, they are on backorder
Im sure someone else has them.