@Phaedrux
Thank you. I currently use Cura 5.5.0. I will look over the several files that have exhibited this issue today but I run those same files on two other machines with no bed heater issues. Only this machine exhibits the unreported fault. That is the reason I believe it is something with this specific motherboard rather than the files. It does have driver0 damage; perhaps an EOS event hurt the processor.
Can anyone suggest any diagnostics I could run while printing that might catch this fault? I'm assuming there is a latch or memory location that holds the "heater active" data. Can that be monitored, and capture what's going on?
Yes Cura calls Reprap during file generation.