I would suspect the Parallax converter has gone bad
Suggest you take it out and drill open the cover then take a close look at the two large capacitors and one smaller one hidden under/behind the heat sink. Your symptoms point to this particular failure.
If your handy with a soldering iron and can locate the parts it's not very difficult or expensive to exchange the defective parts.
If you find it defective and do not want to attempt a fix - Please do not toss it in the trash. I would be happy to pay shipping charges to get to here.