515D kit. Installed and operating perfectly for a couple months. Lately it has started dimming itself when on. For example, if I turn it on at 75%, a couple hours later it will be at 35%. 
 

this particular switch was set on a schedule to come on at 75% every evening for several hours. Day 1 it would come on at 75% then go off at the set time at a much lower %. The next day it would come on at the lower % and then go off at 1%. It happens when used aside from the timer as well. Manually turn on at 100%, several hours later it will be at a much lower %. 
 

I have done a full reset twice. Checked for firmware update. Can't fix the problem.