Thanks for the comments and ideas. BTW, I do have everything powered thru a Furman power conditioner. And I checked the ground wire at the outside cable connection and it is as it should be. I bought additional media converters to isolate the Ethernet on my replacement/repaired gear that wasn't isolated.
I found the fuse on the power supply of the Sony Blu-ray player and it is fine, but the service manual provided instructions to check 2 pins that connect the PS board to the main board for +12v and they both showed nuttin'. So, at least the PS board got zapped and possible more. I haven't a clue on how to repair the PS board and a replacement is $100. The player was only $500 and there they be more trouble if a new PS energizes the other boards and they don't work. Unless someone has a way to test the components on the PS board I guess I'll sell the unit for parts and get something else.
The Marantz is another can of worms. There are a number of boards stuffed on top of the main board and PS board such that disassembly will be quite a task. I think I'll take it to my excellent local repair shop and pay for a diagnosis.
Thanks again everyone.